ARM: mx25: Add basic suspend/resume support

Tested basic suspend/resume on a mx25pdk:

$ echo enabled > /sys/class/tty/ttymxc0/power/wakeup
$ echo mem > /sys/power/state

Then press any key in the serial console and the system wakes up.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
diff --git a/arch/arm/mach-imx/mach-imx25.c b/arch/arm/mach-imx/mach-imx25.c
index 9379fd0..32dcb5e 100644
--- a/arch/arm/mach-imx/mach-imx25.c
+++ b/arch/arm/mach-imx/mach-imx25.c
@@ -41,6 +41,7 @@
 
 DT_MACHINE_START(IMX25_DT, "Freescale i.MX25 (Device Tree Support)")
 	.init_early	= imx25_init_early,
+	.init_late      = imx25_pm_init,
 	.init_irq	= mx25_init_irq,
 	.dt_compat	= imx25_dt_board_compat,
 MACHINE_END