Repair compilation when Pango support is enabled

It seems there have been changes in the way Pango's header files are
installed in recent versions, probably to allow having multiple versions
together on a system.

Because one public header from WINGs has to include Pango's header, we must
include the search path provided by Pango into our WINGs search path that
are returned by pkg-config (the .pc file).

They are then also added to WindowMaker and WPrefs which use the header but
can't rely on the path from the .pc file which has not been installed yet.

Reported-by: Carlos R. Mafra <crmafra@gmail.com>
Signed-off-by: Christophe CURIS <christophe.curis@free.fr>

WINGs/Makefile.am

@@ -107,7 +107,7 @@ WINGs.pc: Makefile
 	@echo 'Requires: wrlib WUtil' >> $@
 	@echo 'Libs: $(lib_search_path) -lWINGs' >> $@
 	@echo 'Libs.private: $(XFT_LIBS) $(PANGOLIBS) $(XLIBS) -lm $(INTLIBS)' >> $@
-	@echo 'Cflags: $(inc_search_path)' >> $@
+	@echo 'Cflags: $(inc_search_path) @PANGO_CFLAGS@' >> $@
 
 WUtil.pc: Makefile
 	@echo "Generating $@"

WPrefs.app/Makefile.am

@@ -45,7 +45,7 @@ WPrefs_SOURCES = \
 #	KeyboardSettings.c \
 #	Themes.c
 
-AM_CFLAGS =
+AM_CFLAGS = @PANGO_CFLAGS@
 
 AM_CPPFLAGS = -DRESOURCE_PATH=\"$(wpdatadir)\" -DWMAKER_RESOURCE_PATH=\"$(pkgdatadir)\" \
 	 -I$(top_builddir)/wrlib -I$(top_srcdir)/WINGs -I$(top_builddir)/WINGs \

src/Makefile.am

@@ -148,7 +148,7 @@ xmodifier.hack_nf.c: xmodifier.c $(top_srcdir)/script/nested-func-to-macro.sh
 endif
 
 
-AM_CFLAGS =
+AM_CFLAGS = @PANGO_CFLAGS@
 
 AM_CPPFLAGS = $(DFLAGS) \
 	-I$(top_builddir)/wrlib \