arm: socfpga: soc64: Add ATF support for Reset Manager driver

In non-secure mode (EL2), Reset Manager driver calls the
SMC/PSCI service provided by ATF to enable/disable the
SOCFPGA bridges.

Signed-off-by: Chee Hong Ang <chee.hong.ang@intel.com>
Signed-off-by: Siew Chin Lim <elly.siew.chin.lim@intel.com>