doxy: suppress erroneous ATTRIBUTE_HELPER_HEADER/CPP warnings

doc/doxygen.warnings.report.sh

@@ -263,6 +263,9 @@ REappend filter_blacklistRE "Schedule(Time"
 REappend filter_blacklistRE "ScheduleWithContext(uint32_t"
 REappend filter_blacklistRE "Schedule\\(Now\\|Destroy\\)(\\(MEM\\|void\\)"
 
+#   ATTRIBUTE_HELPER_CPP( and _HEADER(
+REappend filter_blacklistRE "ATTRIBUTE_HELPER_\\(CPP\\|HEADER\\)("
+
 filter_outRE=""
 if [ $filter_blacklist -eq 1 ]; then
     echo "Filtering out blacklist: \"$filter_blacklistRE\""
@@ -280,6 +283,8 @@ if [ "$filter_out" != "" ] ; then
 fi
 
 #  Show the resulting filters
+echo
+echo "Net result of all filters:"
 if [ "${filter_inRE:-}" != "" ] ; then
     echo "Filtering in \"$filter_inRE\""
 fi