Bug 959768 - Add non-unified mozconfigs for desktop and mobile builds (linux64 bits); r=catlee

browser/config/mozconfigs/linux64/debug

@@ -2,8 +2,6 @@ ac_add_options --enable-debug
 ac_add_options --enable-trace-malloc
 ac_add_options --enable-signmar
 
-ac_add_options --disable-unified-compilation
-
 . $topsrcdir/build/unix/mozconfig.linux
 
 # Needed to enable breakpad in application.ini

browser/config/mozconfigs/linux64/debug-nonunified

+. "$topsrcdir/browser/config/mozconfigs/linux64/debug"
+
+ac_add_options --disable-unified-compilation

browser/config/mozconfigs/linux64/nightly-nonunified

+. "$topsrcdir/browser/config/mozconfigs/linux64/nightly"
+
+ac_add_options --disable-unified-compilation