ARMv7: PSCI: ls102xa: add more PSCI v1.0 functions implemention

ARMv7: PSCI: ls102xa: add more PSCI v1.0 functions implemention

This patch implements PSCI functions for ls102xa SoC following PSCI v1.0,
they are as the list:
    psci_version,
    psci_features,
    psci_cpu_suspend,
    psci_affinity_info,
    psci_system_reset,
    psci_system_off.

Tested on LS1021aQDS, LS1021aTWR.

Signed-off-by: Wang Dongsheng <dongsheng.wang@nxp.com>
Signed-off-by: Hongbo Zhang <hongbo.zhang@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>