libwpd: always set CXXFLAGS

Change-Id: I211f346c428059e20dd1217b5b65fe8c1ab24710
Reviewed-on: https://gerrit.libreoffice.org/43968Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: David Tardon <dtardon@redhat.com>

external/libwpd/ExternalProject_libwpd.mk

@@ -35,7 +35,7 @@ $(call gb_ExternalProject_get_state_target,libwpd,build) :
 			$(if $(filter MACOSX,$(OS)), \
 				--prefix=/@.__________________________________________________OOO) \
 			$(if $(verbose),--disable-silent-rules,--enable-silent-rules) \
-			$(if $(filter TRUE,$(DISABLE_DYNLOADING)),CXXFLAGS="$(CXXFLAGS) $(gb_VISIBILITY_FLAGS) $(gb_VISIBILITY_FLAGS_CXX) $(if $(ENABLE_OPTIMIZED),$(gb_COMPILEROPTFLAGS),$(gb_COMPILERNOOPTFLAGS))") \
+			CXXFLAGS="$(gb_CXXFLAGS) $(if $(ENABLE_OPTIMIZED),$(gb_COMPILEROPTFLAGS),$(gb_COMPILERNOOPTFLAGS))" \
 			CPPFLAGS="$(CPPFLAGS) $(BOOST_CPPFLAGS)" \
 			$(if $(filter LINUX,$(OS)),$(if $(SYSTEM_REVENGE),, \
 				'LDFLAGS=-Wl$(COMMA)-z$(COMMA)origin \