[PATCH] x86-64: Remove fastcall references in x86_64 code

Unlike x86, x86_64 already passes arguments in registers.  The use of
regparm attribute makes no difference in produced code, and the use of
fastcall just bloats the code.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>