sh: turn off irqs when disabling CMT/TMU timers

Modify the CMT and TMU drivers to disable interrupts when
disabling the timer. Only using start/stop bits is not
enough.

This fixes a bootup hang on Migo-R when the CMT is replaced
by TMU for clockevents but the CMT keeps on delivering irqs
even though the timer start bit is off.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index 7135f50..2964f5f 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -184,6 +184,9 @@
 	/* disable channel */
 	sh_cmt_start_stop_ch(p, 0);
 
+	/* disable interrupts in CMT block */
+	sh_cmt_write(p, CMCSR, 0);
+
 	/* stop clock */
 	clk_disable(p->clk);
 }