ARM: OMAP: DRA7: powerdomain data: Fix "ON" state for memories

When the power domain is in "ON" state, the memories should be always
in "ON", even though the hardware register allows other states to be
written, wrong states may confuse certain hardware blocks.

Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>