Merge changes I4451ca03,I29be60ec,Ia30bd332,I72fe2275,I37bd65b0 into integration

* changes:
  feat(plat/nxp/lx2): add SUPPORTED_BOOT_MODE definition
  feat(plat/nxp/common): add build macro for BOOT_MODE validation checking
  refactor(plat/nxp/common): moved soc make-variables to new soc_common_def.mk
  refactor(plat/nxp/lx216x): clean up platform configure file
  refactor(plat/nxp/common): moved plat make-variables to new plat_common_def.mk