ARM: S3C2440: Fix regulator valid_modes_ops on GTA02

The REGULATOR_CHANGE_STATUS flag needs to be set on valid_ops_mask,
otherwise it a driver wont be able to turn the regulator on or off.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>