plat: imx8mm: enable rbc by default for LPM mode

when PLAT(SCU) domain power down is enabled in
WAIT or STOP mode. enable RBC by default to make
sure SCU can be power down successfully even if
the wakeup ITQ is pending.

Signed-off-by: Bai Ping <>
(cherry picked from commit 5cf4479384ba41a01c7f8c63a245215213b11701)
2 files changed