[ARM] 2949/1: Hynix h720x Run mode

Patch from Sascha Hauer

After coming out of idle mode the h720x goes into slow mode. Switch
it back to run mode.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>