File jffi-fix-system-ffi.patch of Package jffi

--- jffi-jffi-1.2.12/jni/GNUmakefile	2016-04-29 23:23:51.000000000 +0200
+++ jffi-jffi-1.2.12/jni/GNUmakefile	2019-04-03 19:52:03.140582936 +0200
@@ -279,7 +279,7 @@
 	@echo "JFFI_BUILD_DIR=$(JFFI_BUILD_DIR)"
 	@echo "OBJS=$(OBJS)"
 
-$(LIBJFFI):  $(OBJS) $(LIBFFI_LIBS)
+$(LIBJFFI):  $(OBJS)
 	$(CC) -o $@ $(LDFLAGS) $(SOFLAGS) $(OBJS) $(LIBFFI_LIBS) $(LIBS)
 	$(STRIP) $@
 
@@ -291,7 +291,9 @@
 	@mkdir -p $(@D)
 	@$(CC) $(CFLAGS) -o $@ -c $<
 
+ifneq ($(USE_SYSTEM_LIBFFI),1)
 $(OBJS) : $(LIBFFI_LIBS)
+endif
 
 ifeq ($(OS), darwin)
 build_ffi = \