Merge changes from topic "af/add_branch_protection_makefiles"

* changes:
  TFTF: Add ARMv8.5 BTI support in makefiles
  TFTF: Add ARMv8.5 BTI support in xlat_tables_v2 library
  TFTF: Add ARMv8.5 BTI support in assembler files
  TFTF: Add ARMv8.5 BTI-related definitions