libzmf: pass optimization flags to configure

Change-Id: Iff6558155100817f045053a781d09eedcd6724a2
Reviewed-on: https://gerrit.libreoffice.org/44007Reviewed-by: David Tardon <dtardon@redhat.com>
Tested-by: David Tardon <dtardon@redhat.com>

external/libzmf/ExternalProject_libzmf.mk

@@ -37,6 +37,7 @@ $(call gb_ExternalProject_get_state_target,libzmf,build) :
 			--disable-werror \
 			--disable-weffc \
 			$(if $(verbose),--disable-silent-rules,--enable-silent-rules) \
+			CXXFLAGS="$(gb_CXXFLAGS) $(if $(ENABLE_OPTIMIZED),$(gb_COMPILEROPTFLAGS),$(gb_COMPILERNOOPTFLAGS))" \
 			CPPFLAGS="$(CPPFLAGS) $(BOOST_CPPFLAGS)" \
 			$(if $(CROSS_COMPILING),--build=$(BUILD_PLATFORM) --host=$(HOST_PLATFORM)) \
 		&& $(MAKE) \