Patch to make openbsc find libsmpp34

This patch lets the build script for openbsc find the libsmpp34 installation
with the help of pkg-config instead of assuming the header files are in
/usr/include.
diff --git a/openbsc/tests/smpp/Makefile.am b/openbsc/tests/smpp/Makefile.am
index 06e7af6..9ab15c5 100644
--- a/openbsc/tests/smpp/Makefile.am
+++ b/openbsc/tests/smpp/Makefile.am
@@ -1,5 +1,5 @@
 AM_CPPFLAGS = $(all_includes) -I$(top_srcdir)/include -I$(top_srcdir)/src/libmsc
-AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS) $(LIBOSMOSCCP_CFLAGS) $(LIBOSMOABIS_CFLAGS) $(COVERAGE_CFLAGS)
+AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS) $(LIBOSMOSCCP_CFLAGS) $(LIBOSMOABIS_CFLAGS) $(COVERAGE_CFLAGS) $(LIBSMPP34_CFLAGS)
 AM_LDFLAGS = $(COVERAGE_LDFLAGS)
 
 EXTRA_DIST = smpp_test.ok smpp_test.err