os iOS 11.4 to 12.0 API Differences

availability.h
Added #def SPI_AVAILABLE
lock.h
signpost.h
Added #def os_signpost_id_make_with_id
Added #def OS_LOG_CATEGORY_POINTS_OF_INTEREST
Added #def os_signpost_emit_with_type
trace_base.h
Added #def OS_LOG_CALL_WITH_FORMAT_NAME