fix build if depenedencies are in distinct directories
diff --git a/src/Makefile.am b/src/Makefile.am
index 27e0e19..00af272 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -3,7 +3,7 @@
ASN1_ROOT = $(top_builddir)/asn1/
ASN1TOSTRUCT = $(ASN1_ROOT)/utils/asn1tostruct.py
-AM_CFLAGS = $(OSMOCORE_CFLAGS) $(OSMOVTY_CFLAGS) $(OSMOGSM_CFLAGS) $(ASN1C_CFLAGS) $(OSMOSIGTRAN_CFLAGS) -Ihnbap/
+AM_CFLAGS = $(OSMOCORE_CFLAGS) $(OSMOVTY_CFLAGS) $(OSMOGSM_CFLAGS) $(OSMONETIF_CFLAGS) $(ASN1C_CFLAGS) $(OSMOSIGTRAN_CFLAGS) -Ihnbap/
COMMON_LDADD = -lsctp
bin_PROGRAMS = hnbgw