[ARM] 3945/1: AT91: Rename devices.c

This patch renames the arch/arm/mach-at91rm9200/devices.c file to
at91rm9200_devices.c.  The file contains AT91RM9200-specific code, so we
will need separate files for the SAM9 processors.

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