For different host and target archs, try to check whether
their compilers support '-m32' option individually. If yes,
then add this option into cflags and ldflags. The exception is
that both host and target archs are 'x64'.

Review URL: https://chromiumcodereview.appspot.com/10335014
Patch from Yongsheng Zhu <yongsheng.zhu@intel.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11597 ce2b1a6d-e550-0410-aec6-3dcde31c8c00