[ARM] 3977/1: AT91: remove loop waiting for reset

Removed the infinite loop in our arch_reset().

After calling arch_reset(), the kernel waits for 1 second before
printing a "reboot failed" message and then waits for ever itself.

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