src/Makefile: Change order of dependencies so a clean checkout builds

There still seem to be some issues with the _decode.o dependencies, but
this will eventually build through.
diff --git a/src/Makefile b/src/Makefile
index 67e6e98..f5e4bd3 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -38,7 +38,7 @@
 ranap/libosmo-asn1-ranap.a:
 	$(MAKE) -C ranap
 
-hnbgw: iu_helpers.o asn1helpers.o hnbgw.o hnbgw_hnbap.o hnbgw_rua.o hnbgw_ranap.o $(HNBAP_OBJS) $(RUA_OBJS) $(RANAP_OBJS) $(LIBS)
+hnbgw: 	$(HNBAP_OBJS) $(RUA_OBJS) $(RANAP_OBJS) iu_helpers.o asn1helpers.o hnbgw.o hnbgw_hnbap.o hnbgw_rua.o hnbgw_ranap.o $(LIBS)
 	$(CC) $(LDFLAGS) -o $@ $^
 
 %.o: %.c