[ARM] 4124/1: Rename mach-at91rm9200 and arch-at91rm9200 directories

Now that Linux includes support for the Atmel AT91SAM9260 and
AT91SAM9261 processors in addition to the original Atmel AT91RM9200
(with support for more AT91 processors pending), the "mach-at91rm9200"
and "arch-at91rm9200" directories should be renamed to indicate their
more generic nature.

The following git commands should be run BEFORE applying this patch:
  git-mv arch/arm/mach-at91rm9200 arch/arm/mach-at91
  git-mv include/asm-arm/arch-at91rm9200 include/asm-arm/arch-at91

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