[ARM] 3675/2: Preparing for AT91SAM926 support

Patch from Andrew Victor

This prepares the way for adding support for the new Atmel AT91SAM926x
processors.

Major changes:
- Rename time.c to at91rm9200_time.c
- Rename common.c to at91rm9200.c
- Introduce ARCH_AT91, of which ARCH_AT91RM9200, ARCH_AT91SAM9260 and
ARCH_AT91SAM9261 are dependent.

Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/configs/at91rm9200dk_defconfig b/arch/arm/configs/at91rm9200dk_defconfig
index 9e1c1cc..4f3d8d3 100644
--- a/arch/arm/configs/at91rm9200dk_defconfig
+++ b/arch/arm/configs/at91rm9200dk_defconfig
@@ -103,6 +103,7 @@
 # CONFIG_ARCH_IMX is not set
 # CONFIG_ARCH_H720X is not set
 # CONFIG_ARCH_AAEC2000 is not set
+CONFIG_ARCH_AT91=y
 CONFIG_ARCH_AT91RM9200=y
 
 #