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>
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index ddf2cc5..d90fb89 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -313,6 +313,9 @@
 config CPU_HAS_PINT_IRQ
 	bool
 
+config CPU_HAS_MASKREG_IRQ
+	bool
+
 config CPU_HAS_INTC2_IRQ
 	bool