fontconfig: don't use gb_ExternalProject_use_packages directly

Change-Id: I4ebe1a8caded065043db997e34d5d2b205fcca20

RepositoryExternal.mk

@@ -1041,6 +1041,8 @@ $(call gb_LinkTarget_add_libs,$(1),$(FREETYPE_LIBS))
 
 endef
 
+gb_ExternalProject__use_freetype :=
+
 else ifeq ($(OS),ANDROID)
 
 define gb_LinkTarget__use_freetype_headers
@@ -1056,6 +1058,11 @@ $(call gb_LinkTarget_use_external,$(1),freetype_headers)
 
 endef
 
+define gb_ExternalProject__use_freetype
+$(call gb_ExternalProject_use_package,$(1),freetype)
+
+endef
+
 endif # SYSTEM_FREETYPE
 
 ifeq ($(SYSTEM_FONTCONFIG),YES)

fontconfig/ExternalProject_fontconfig.mk

@@ -9,7 +9,7 @@
 
 $(eval $(call gb_ExternalProject_ExternalProject,fontconfig))
 
-$(eval $(call gb_ExternalProject_use_packages,fontconfig,\
+$(eval $(call gb_ExternalProject_use_externals,fontconfig,\
 	expat \
 	freetype \
 ))