On i.MX8QM/i.MX8QX with system controller inside, the wakeup
source is managed in SCFW(system controller firmware), if the
wakeup source is belonged to system controller partition, then
before Linux suspend, the wakeup source should be set to
SC_PM_WAKE_SRC_SCU, and if the wakeup source is belonged to
Cortex-A partition, the wakeup source should be set to
SC_PM_WAKE_SRC_IRQSTEER, so need to add wakeup source SIP runtime
service to get Linux kernel's wakeup source and set the correct
wakeup source for system controller.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>