sh: maskreg IRQ support.

Formerly implemented by ADX, we can use this generically,
so move it over.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/kernel/cpu/irq/Makefile

@@ -3,5 +3,6 @@
 #
 obj-y	+= ipr.o imask.o
 
-obj-$(CONFIG_CPU_HAS_PINT_IRQ)	+= pint.o
-obj-$(CONFIG_CPU_HAS_INTC2_IRQ)	+= intc2.o
+obj-$(CONFIG_CPU_HAS_PINT_IRQ)		+= pint.o
+obj-$(CONFIG_CPU_HAS_MASKREG_IRQ)	+= maskreg.o
+obj-$(CONFIG_CPU_HAS_INTC2_IRQ)		+= intc2.o