ARMv8/sec_firmware: relocated and renamed the config FSL_PPA_ARMV8_PSCI

Moved the config FSL_PPA_ARMV8_PSCI from fsl-layerscape's Kconfig to
Kconfig under armv8 and renamed it to SEC_FIRMWARE_ARMV8_PSCI.

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
10 files changed