devel/glademm: Fix build with llvm16

- Pet portclippy

Approved by:	portmgr (blanket)
Sponsored by:	The FreeBSD Foundation

devel/glademm/Makefile

@@ -10,18 +10,18 @@ COMMENT=	C++ code generator backend for glade and glade2
 WWW=		http://home.wtal.de/petig/Gtk/
 
 USES=		gmake gnome pathfix pkgconfig
+USE_CXXSTD=	c++14
 USE_GNOME=	gnomeprefix
+
 GNU_CONFIGURE=	yes
 
 PLIST_FILES=	bin/glade-- bin/glademm-embed
 
-.include <bsd.port.pre.mk>
-
 post-patch:
 	@${RM} ${WRKSRC}/src/getopt.*
 	@${REINPLACE_CMD} \
 		-Ee '/^@AMDEP/!s|getopt([^[:space:]])+||g' \
 		-Ee '/^@AMDEP(.)+getopt/d' \
 			${WRKSRC}/src/Makefile.in
 
-.include <bsd.port.post.mk>
+.include <bsd.port.mk>