Remove strange v8_target_arch=="mac" conditions from gyp files

mac is not an architecture, and it doesn't make sense to compile in both
the ia32 and x64 archs at the same time

BUG=none
R=jkummerow@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/255183002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21176 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

tools/gyp/v8.gyp

@@ -696,7 +696,7 @@
             '../../src/arm64/utils-arm64.h',
           ],
         }],
-        ['v8_target_arch=="ia32" or v8_target_arch=="mac" or OS=="mac"', {
+        ['v8_target_arch=="ia32"', {
           'sources': [  ### gcmole(arch:ia32) ###
             '../../src/ia32/assembler-ia32-inl.h',
             '../../src/ia32/assembler-ia32.cc',
@@ -761,7 +761,7 @@
             '../../src/mips/stub-cache-mips.cc',
           ],
         }],
-        ['v8_target_arch=="x64" or v8_target_arch=="mac" or OS=="mac"', {
+        ['v8_target_arch=="x64"', {
           'sources': [  ### gcmole(arch:x64) ###
             '../../src/x64/assembler-x64-inl.h',
             '../../src/x64/assembler-x64.cc',