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/channel/Makefile.am b/openbsc/tests/channel/Makefile.am
index 6b9f6e3..8e57b8d 100644
--- a/openbsc/tests/channel/Makefile.am
+++ b/openbsc/tests/channel/Makefile.am
@@ -8,14 +8,8 @@
 	$(top_srcdir)/src/gsm_subscriber_base.c \
 	$(top_srcdir)/src/gsm_subscriber.c \
 	$(top_srcdir)/src/debug.c \
-	$(top_srcdir)/src/timer.c \
-	$(top_srcdir)/src/select.c \
-	$(top_srcdir)/src/talloc.c \
 	$(top_srcdir)/src/gsm_data.c \
-	$(top_srcdir)/src/signal.c \
-	$(top_srcdir)/src/statistics.c \
 	$(top_srcdir)/src/bts_ipaccess_nanobts.c \
-	$(top_srcdir)/src/bts_siemens_bs11.c \
-	$(top_srcdir)/src/tlv_parser.c
-channel_test_LDADD = -ldl -ldbi
+	$(top_srcdir)/src/bts_siemens_bs11.c
+channel_test_LDADD = -ldl -ldbi $(LIBOSMOCORE_LIBS)