Bug 1796380 - Don't add -pie to LDFLAGS on mac. r=firefox-build-system-reviewers,sergesanspaille

It's the default and clang complains the argument is unused.

Differential Revision: https://phabricator.services.mozilla.com/D178733

build/autoconf/compiler-opts.m4

@@ -146,7 +146,9 @@ if test "$GNU_CC" -a "$GCC_USE_GNU_LD" -a -z "$DEVELOPER_OPTIONS" -a -z "$MOZ_PR
 fi
 
 if test "$GNU_CC$CLANG_CC"; then
-    MOZ_PROGRAM_LDFLAGS="$MOZ_PROGRAM_LDFLAGS -pie"
+    if "${OS_TARGET}" != Darwin; then
+        MOZ_PROGRAM_LDFLAGS="$MOZ_PROGRAM_LDFLAGS -pie"
+    fi
 fi
 
 AC_SUBST(MOZ_PROGRAM_LDFLAGS)