This patch adds the support for cpuidle on AT91 SoCs, taken from the
cpuidle support in mach-kirkwood.
cpuidle needs sdram_selfrefresh_enable and _disable, so move their
definition to a separate header file instead of duplicating the code
already used in pm.c.
Tested-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NAlbin Tonnerre <albin.tonnerre@free-electrons.com>
Acked-by: NAndrew Victor <linux@maxim.org.za>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The patch adds support for Kirkwood cpu idle.
Two idle states are defined:
1. Wait-for-interrupt (replacing default kirkwood wfi)
2. Wait-for-interrupt and DDR self refresh
Signed-off-by: NRabeeh Khoury <rabeeh@marvell.com>
Signed-off-by: NNicolas Pitre <nico@marvell.com>