[ARM] 4427/1: base Atmel at91x40 architecture defines

Base at91x40 architecture support defines. These parts are somewhat
simpler than the ARM9 Atmel based parts.

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