hnbgw: Add SUA client socket towards localhost

This socket doesn't do much yet except to connect to localhost:14001

The host/port needs to be made configurable, and the RUA<->SUA
interfacing needs to be implemented.

Also, we'll need two SUA sockets, one for MSC and one for SGSN.
diff --git a/src/Makefile.am b/src/Makefile.am
index ec7250b..cbafe8a 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -3,13 +3,13 @@
 ASN1_ROOT = $(top_builddir)/asn1/
 ASN1TOSTRUCT = $(ASN1_ROOT)/utils/asn1tostruct.py
 
-AM_CFLAGS = $(OSMOCORE_CFLAGS) $(OSMOVTY_CFLAGS) $(OSMOGSM_CFLAGS) $(ASN1C_CFLAGS) -Ihnbap/
+AM_CFLAGS = $(OSMOCORE_CFLAGS) $(OSMOVTY_CFLAGS) $(OSMOGSM_CFLAGS) $(ASN1C_CFLAGS) $(OSMOSIGTRAN_CFLAGS) -Ihnbap/
 COMMON_LDADD = -lsctp
 
 bin_PROGRAMS = hnbgw
 
 hnbgw_SOURCES = hnbap_encoder.c hnbap_decoder.c rua_encoder.c rua_decoder.c ranap_common.c rua_common.c hnbap_common.c iu_helpers.c asn1helpers.c hnbgw.c hnbgw_hnbap.c hnbgw_rua.c hnbgw_ranap.c ranap_decoder.c ranap_encoder.c ranap_msg_factory.c
-hnbgw_LDADD = $(OSMOCORE_LIBS) $(OSMOVTY_LIBS) $(OSMOGSM_LIBS) $(ASN1C_LIBS) $(COMMON_LDADD) hnbap/libosmo-asn1-hnbap.a rua/libosmo-asn1-rua.a ranap/libosmo-asn1-ranap.a
+hnbgw_LDADD = $(OSMOCORE_LIBS) $(OSMOVTY_LIBS) $(OSMOGSM_LIBS) $(ASN1C_LIBS) $(OSMOSIGTRAN_LIBS) $(COMMON_LDADD) hnbap/libosmo-asn1-hnbap.a rua/libosmo-asn1-rua.a ranap/libosmo-asn1-ranap.a
 
 BUILT_SOURCES = hnbap_decoder.c hnbap_encoder.c rua_decoder.c rua_encoder.c ranap_decoder.c ranap_encoder.c