Make CONFIG_REGPARM enabled by default.  It's a noticable win both for size
and for performance, and gcc[34] handles it correctly.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>