Revert "mmx: Use MMX2 intrinsics from xmmintrin.h directly."

This reverts commit 7de61d8d14e84623b6fa46506eb74f938287f536.

Newer versions of gcc allow inclusion of xmmintrin.h without -msse, but
still won't allow usage of the intrinsics.

Bugzilla: https://bugs.gentoo.org/show_bug.cgi?id=564024
2 files changed