Merge changes from topic "soc_id" into integration

* changes:
  refactor(plat/nvidia): use SOC_ID defines
  refactor(plat/mediatek): use SOC_ID defines
  refactor(plat/arm): use SOC_ID defines
  feat(plat/st): implement platform functions for SMCCC_ARCH_SOC_ID
  refactor(plat/st): export functions to get SoC information
  feat(smccc): add bit definition for SMCCC_ARCH_SOC_ID