ARM: move reboot code to arch/arm/kernel/reboot.c

Move shutdown and reboot related code to a separate file, out of
process.c.  This helps to avoid polluting process.c with non-process
related code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --cc arch/arm/kernel/Makefile
Simple merge

diff --cc arch/arm/kernel/hibernate.c
Simple merge

diff --cc arch/arm/kernel/process.c
Simple merge

diff --cc arch/arm/kernel/reboot.c
Simple merge

diff --cc arch/arm/kernel/reboot.h
Simple merge