sh: fix compressed kernel build

commit 54a01510 broke zImage build on sh arch:

 LD      vmlinux
  SYSMAP  System.map
  SYSMAP  .tmp_System.map
  AS      arch/sh/boot/compressed/head_32.o
In file included from /k/arch/sh/boot/compressed/head_32.S:11:
/k/include/linux/linkage.h:34: error: syntax error in macro parameter list

Fix it for both sh and sh64.

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>