ARM: mach-shmobile: add fixed voltage regulators to marzen

On marzen provide a dummy regulator for the smsc911x driver.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>