sysreset: Implement PSCI based reset to EDL mode for QCOM SoCs

sysreset: Implement PSCI based reset to EDL mode for QCOM SoCs

Implement request_arg() sysreset_op for QCOM SoCs that use
PSCI to reset to EDL (Emergency Download) mode.

Reviewed-by: Casey Connolly <casey.connolly@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Signed-off-by: Varadarajan Narayanan <varadarajan.narayanan@oss.qualcomm.com>
Link: https://patch.msgid.link/20260121063920.1500293-4-varadarajan.narayanan@oss.qualcomm.com
[casey: add missing ARM_SMCCC depends to kconfig to fix CI allyesconfig]
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>