Fix build on GCC-based systems:

cc1plus: error: unrecognized command line option "-msse"
cc1plus: error: unrecognized command line option "-msse2"
cc1plus: error: unrecognized command line option "-std=gnu++0x"

The previous patchfile is now split into two, depending on whether
ARCH is x86 or not.

Since REINPLACE is now deprecated for this purpose, I could not
figure out any other way to do it.

Approved by: portmgr (tier-2 blanket)