devel/pango buld problems on macOS 11

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

Trying to build devel/pango on macOS 11 (with LIBRSVG_TYPE=c) fails because
1) harfbuzz seems to use C++1 features
2) harfbuzz seems to require graphite2 even with C LIBRSVG

Index: Makefile
===================================================================
RCS file: /cvsroot/pkgsrc/devel/pango/Makefile,v
retrieving revision 1.236
diff -u -r1.236 Makefile
--- Makefile	15 Sep 2020 10:45:41 -0000	1.236
+++ Makefile	29 Dec 2020 12:22:06 -0000
@@ -12,7 +12,7 @@
 
 TOOL_DEPENDS+=		help2man-[0-9]*:../../converters/help2man
 
-USE_LANGUAGES=		c c++
+USE_LANGUAGES=		c c++ c++11
 USE_TOOLS+=		gmake pkg-config
 INSTALLATION_DIRS=	${PKGMANDIR}/man1
 
@@ -56,9 +56,7 @@
 .include "../../fonts/fontconfig/buildlink3.mk"
 BUILDLINK_API_DEPENDS.harfbuzz+= harfbuzz>=2.7.2
 .include "../../fonts/harfbuzz/buildlink3.mk"
-.if ${LIBRSVG_TYPE} == "rust"
 .include "../../graphics/graphite2/buildlink3.mk"
-.endif
 BUILDLINK_API_DEPENDS.cairo+=	cairo>=1.12.10
 .include "../../graphics/cairo/buildlink3.mk"
 .include "../../graphics/cairo-gobject/buildlink3.mk"

The package also seems not to install pangocoretext.h, but I'm not sure 
if that's an error when building or an error in PLIST.