build: use $top_srcdir instead of ../
diff --git a/src/Makefile.am b/src/Makefile.am
index b0badc3..615b838 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -20,7 +20,7 @@
# this is ugly ^. ranap_ies_defs.h is generated from asn1tostruct.py here, but
# it should live in include/osmocom/ranap/.
-AM_CFLAGS = -I../include $(OSMOCORE_CFLAGS) $(OSMOVTY_CFLAGS) $(OSMOGSM_CFLAGS) $(OSMONETIF_CFLAGS) $(ASN1C_CFLAGS) $(OSMOSIGTRAN_CFLAGS)
+AM_CFLAGS = -I$(top_srcdir)/include $(OSMOCORE_CFLAGS) $(OSMOVTY_CFLAGS) $(OSMOGSM_CFLAGS) $(OSMONETIF_CFLAGS) $(ASN1C_CFLAGS) $(OSMOSIGTRAN_CFLAGS)
COMMON_LDADD = -lsctp
# build the shared RANAP library