[ARM] 3865/1: AT91RM9200 header updates

This is more preparation for adding support for the new Atmel AT91SAM9
processors.

Changes include:
- Replace AT91_BASE_* with AT91RM9200_BASE_*
- Replace AT91_ID_* with AT91RM9200_ID_*
- ROM, SRAM and UHP address definitions moved to at91rm9200.h.
- The raw AT91_P[ABCD]_* definitions are now depreciated in favour of
the GPIO API.

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