finish openbsc / libosmocore separation

* use pkg-config from openbsc to find header and library
* move sms and timer tests to libosmocore itself
* ensure "make distcheck" works on both packages
diff --git a/openbsc/tests/gsm0408/Makefile.am b/openbsc/tests/gsm0408/Makefile.am
index 69f1e4e..44ca96c 100644
--- a/openbsc/tests/gsm0408/Makefile.am
+++ b/openbsc/tests/gsm0408/Makefile.am
@@ -2,4 +2,4 @@
 noinst_PROGRAMS = gsm0408_test
 
 gsm0408_test_SOURCES = gsm0408_test.c
-gsm0408_test_LDADD = $(top_builddir)/src/libbsc.a $(top_builddir)/src/libmsc.a $(top_builddir)/src/libbsc.a $(top_builddir)/src/liblaf0rge1.a -ldbi
+gsm0408_test_LDADD = $(top_builddir)/src/libbsc.a $(top_builddir)/src/libmsc.a $(top_builddir)/src/libbsc.a $(LIBOSMOCORE_LIBS) -ldbi