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Add following APIs in plat_psci to support system shutdown & reset:
- versal_system_off
- versal_system_reset
Signed-off-by: Saeed Nowshadi <saeed.nowshadi@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Change-Id: Ia2c1a19ded18984b393e1fdee760bf48b45e9902