Add assembler equivalents to __init{,date}_refok

I need __INIT_REFOK to fix a MODPOST warning for a few MIPS configs which
have to call init code from .text very early in the game due to bootloader
issues.  __INITDATA_REFOK is just for consistency.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>