[ARM] 4906/1: [AT91] SAM9/CAP9 basic power-management

Basic power-management (suspend-to-ram) support for Atmel SAM9 and
CAP9 processors.

Based on comments & patches from Anti Sullin and David Brownell.

Signed-off-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>