Install only one of the two mingw architectures in appveyor

Closes ticket 27765

This commit also changes the appveyor file to a unified line ending
style, since the old one was pretty confused.  Use "-b" to see the
real differences.

.appveyor.yml

-version: 1.0.{build}
-
-clone_depth: 50
-
-environment:
-  compiler: mingw
-
-  matrix:
-  - target: i686-w64-mingw32
-    compiler_path: mingw32
-    openssl_path: /c/OpenSSL-Win32
-    hardening:
-  - target: x86_64-w64-mingw32
-    compiler_path: mingw64
-    openssl_path: /c/OpenSSL-Win64
-    hardening: --disable-gcc-hardening
-
-install:
-- ps: >-
-    Function Execute-Command ($commandPath)
-    {
-        & $commandPath $args 2>&1
-        if ( $LastExitCode -ne 0 ) {
-            $host.SetShouldExit( $LastExitCode )
-        }
-    }
-    Function Execute-Bash ()
-    {
-        Execute-Command 'c:\msys64\usr\bin\bash' '-e' '-c' $args
-    }
-    Execute-Command "C:\msys64\usr\bin\pacman" -Sy --needed --noconfirm openssl-devel openssl libevent-devel libevent mingw-w64-i686-libevent mingw-w64-x86_64-libevent mingw-w64-i686-openssl mingw-w64-x86_64-openssl mingw-w64-i686-zstd mingw-w64-x86_64-zstd
-
-build_script:
-- ps: >-
-    if ($env:compiler -eq "mingw") {
-            $oldpath = ${env:Path} -split ';'
-            $buildpath = @("C:\msys64\${env:compiler_path}\bin", "C:\msys64\usr\bin") + $oldpath
-            $env:Path = @($buildpath) -join ';'
-            $env:build = @("${env:APPVEYOR_BUILD_FOLDER}", $env:target) -join '\'
-            Set-Location "${env:APPVEYOR_BUILD_FOLDER}"
-            Execute-Bash 'autoreconf -i'
-            mkdir "${env:build}"
-            Set-Location "${env:build}"
-            Execute-Bash "which ${env:target}-gcc"
-            Execute-Bash "${env:target}-gcc --version"
-            Execute-Bash "../configure --prefix=/${env:compiler_path} --build=${env:target} --host=${env:target} --disable-asciidoc --enable-fatal-warnings --with-openssl-dir=${env:openssl_path} ${env:hardening}"
-            Execute-Bash "V=1 make -j2"
-            Execute-Bash "V=1 make -j2 install"
-     }
-
-test_script:
-- ps: >-
-    if ($env:compiler -eq "mingw") {
-            $oldpath = ${env:Path} -split ';'
-            $buildpath = @("C:\msys64\${env:compiler_path}\bin") + $oldpath
-            $env:Path = $buildpath -join ';'
-            Set-Location "${env:build}"
-            Execute-Bash "VERBOSE=1 make -j2 check"
-    }
-
-on_failure:
-- ps: >-
-    if ($env:compiler -eq "mingw") {
-            $oldpath = ${env:Path} -split ';'
-            $buildpath = @("C:\msys64\usr\bin") + $oldpath
-            $env:Path = @($buildpath) -join ';'
-            Set-Location "${env:build}"
-            Execute-Bash "7z a logs.zip config.log || true"
-            Execute-Bash "7z a logs.zip test-suite.log || true"
-            Execute-Bash "appveyor PushArtifact logs.zip || true"
-            Execute-Bash "tail -1000 config.log || true"
-            Execute-Bash "cat test-suite.log || true"
-    }
-- cmd: C:\Python27\python.exe %APPVEYOR_BUILD_FOLDER%\scripts\test\appveyor-irc-notify.py irc.oftc.net:6697 tor-ci failure
+version: 1.0.{build}
+
+clone_depth: 50
+
+environment:
+  compiler: mingw
+
+  matrix:
+  - target: i686-w64-mingw32
+    compiler_path: mingw32
+    openssl_path: /c/OpenSSL-Win32
+    mingw_prefix: mingw-w64-i686
+    hardening:
+  - target: x86_64-w64-mingw32
+    compiler_path: mingw64
+    openssl_path: /c/OpenSSL-Win64
+    mingw_prefix: mingw-w64-x86_64
+    hardening: --disable-gcc-hardening
+
+install:
+- ps: >-
+    Function Execute-Command ($commandPath)
+    {
+        & $commandPath $args 2>&1
+        if ( $LastExitCode -ne 0 ) {
+            $host.SetShouldExit( $LastExitCode )
+        }
+    }
+    Function Execute-Bash ()
+    {
+        Execute-Command 'c:\msys64\usr\bin\bash' '-e' '-c' $args
+    }
+    Execute-Command "C:\msys64\usr\bin\pacman" -Sy --needed --noconfirm openssl-devel openssl libevent-devel libevent ${env:mingw_prefix}-libevent ${env:mingw_prefix}-openssl ${env:mingw_prefix}-zstd
+
+build_script:
+- ps: >-
+    if ($env:compiler -eq "mingw") {
+            $oldpath = ${env:Path} -split ';'
+            $buildpath = @("C:\msys64\${env:compiler_path}\bin", "C:\msys64\usr\bin") + $oldpath
+            $env:Path = @($buildpath) -join ';'
+            $env:build = @("${env:APPVEYOR_BUILD_FOLDER}", $env:target) -join '\'
+            Set-Location "${env:APPVEYOR_BUILD_FOLDER}"
+            Execute-Bash 'autoreconf -i'
+            mkdir "${env:build}"
+            Set-Location "${env:build}"
+            Execute-Bash "which ${env:target}-gcc"
+            Execute-Bash "${env:target}-gcc --version"
+            Execute-Bash "../configure --prefix=/${env:compiler_path} --build=${env:target} --host=${env:target} --disable-asciidoc --enable-fatal-warnings --with-openssl-dir=${env:openssl_path} ${env:hardening}"
+            Execute-Bash "V=1 make -j2"
+            Execute-Bash "V=1 make -j2 install"
+     }
+
+test_script:
+- ps: >-
+    if ($env:compiler -eq "mingw") {
+            $oldpath = ${env:Path} -split ';'
+            $buildpath = @("C:\msys64\${env:compiler_path}\bin") + $oldpath
+            $env:Path = $buildpath -join ';'
+            Set-Location "${env:build}"
+            Execute-Bash "VERBOSE=1 make -j2 check"
+    }
+
+on_failure:
+- ps: >-
+    if ($env:compiler -eq "mingw") {
+            $oldpath = ${env:Path} -split ';'
+            $buildpath = @("C:\msys64\usr\bin") + $oldpath
+            $env:Path = @($buildpath) -join ';'
+            Set-Location "${env:build}"
+            Execute-Bash "7z a logs.zip config.log || true"
+            Execute-Bash "7z a logs.zip test-suite.log || true"
+            Execute-Bash "appveyor PushArtifact logs.zip || true"
+            Execute-Bash "tail -1000 config.log || true"
+            Execute-Bash "cat test-suite.log || true"
+    }
+- cmd: C:\Python27\python.exe %APPVEYOR_BUILD_FOLDER%\scripts\test\appveyor-irc-notify.py irc.oftc.net:6697 tor-ci failure