Change WIN32 to _M_IX86 and use YUV_DISABLE_ASM consistently
BUG=none
TEST=none
Review URL: http://webrtc-codereview.appspot.com/277008

git-svn-id: http://libyuv.googlecode.com/svn/trunk@84 16f28f9a-4ce2-e073-06de-1de4eb20be90
7 files changed