move to libcommon-cs: net init 3: actual move

Reincarnate gsm_network_init() as the parts not specific to libbsc.
Move from bsc_network_init() those bits that are not BSC specific (and useful
for upcoming osmo-cscn).

Add libcommon-cs to all linkages that use gsm_network_init().

Note: the only requirement to allow linking gsm_network_init() without libbsc
is to keep the call to gsm_net_update_ctype() out of libcommon-cs. The other items
are kept out of libcommon-cs because it makes sense semantically. But the separation
is not strong in that the BSC specific data members are of course still
omnipresent in struct gsm_network. If bsc_network_init() is not called, these
are not initialized properly -- for now no users of uninitialized members
exist.

So this is just a first step towards a sensible split of the BSC and MSC
gsm_network structs. The long term aim should be to have entirely separate
structs with some common general items.

Change-Id: If06316b97002390dc9a434686750cb96193ea63b
diff --git a/openbsc/tests/bsc-nat/Makefile.am b/openbsc/tests/bsc-nat/Makefile.am
index fa55d27..40be3a3 100644
--- a/openbsc/tests/bsc-nat/Makefile.am
+++ b/openbsc/tests/bsc-nat/Makefile.am
@@ -44,6 +44,7 @@
 bsc_nat_test_LDADD = \
 	$(top_builddir)/src/libfilter/libfilter.a \
 	$(top_builddir)/src/libbsc/libbsc.a \
+	$(top_builddir)/src/libcommon-cs/libcommon-cs.a \
 	$(top_builddir)/src/libmgcp/libmgcp.a \
 	$(top_builddir)/src/libtrau/libtrau.a \
 	$(top_builddir)/src/libcommon/libcommon.a \