Make the use of asmlinkage like the rest of the kernel.

Link: http://lkml.kernel.org/r/efb2dfed4d9315bf68ec0334c81b65af176a0174.1499284835.git.joe@perches.comSigned-off-by: Joe Perches <joe@perches.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>