merge revision(s) bcb32470,fe0225ff: [Backport #19778]

	[Bug #19778] Pass additional include options to INCFLAGS in common.mk

	---
	 common.mk            | 2 +-
	 configure.ac         | 1 +
	 template/Makefile.in | 1 +
	 3 files changed, 3 insertions(+), 1 deletion(-)

	[Bug #19778] Add `-I` options for opt-dir to `$INCFLAGS`

	These options have been separated from `$CFLAGS` already in the
	other places.
	---
	 configure.ac | 2 +-
	 1 file changed, 1 insertion(+), 1 deletion(-)