sh: define GENERIC_HARDIRQS_NO__DO_IRQ.

We haven't called in to __do_IRQ() in a long time, so it seems like a
reasonable time to switch this on by default.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/Kconfig

@@ -48,6 +48,9 @@ config GENERIC_HWEIGHT
 config GENERIC_HARDIRQS
 	def_bool y
 
+config GENERIC_HARDIRQS_NO__DO_IRQ
+	def_bool y
+
 config GENERIC_IRQ_PROBE
 	def_bool y