The new out of line put_user() assembly on x86_64 changes %rcx without
telling GCC about it causing things like:

http://bugme.osdl.org/show_bug.cgi?id=4515 

See to it that %rcx is not changed (made it consistent with get_user()).
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: ak@suse.de
Signed-off-by: Linus Torvalds <torvalds@osdl.org>