x86: Only make Macintosh drivers default on Macs

It's already annoying that they appear on x86 now -- that's for the 3button
emulation needed on x86 macs -- but at least don't make them default.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>