linux-wandboard

MLK-16351 rtc: imx-sc: use SIP to set RTC time

For system controller RTC, as it belongs SC_R_SYSTEM,
and SC_R_SYSTEM is assigned in ARM-Trusted-Firmware,
so here needs to use SIP to trap into ATF to do set
time, or system controller firmware will return
error since linux kernel does NOT own this system
resource.

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