Move timezone settings up to network level

Time zone used to be configurable per-BTS. In the upcoming MSC-split, no BTS
structures will be available on the MSC level. To simplify, drop the ability to
manage several time zones in a core network and place the time zone config on
the network VTY level, i.e. in gsm_network. If we are going to re-add fine
grained time zone settings, it should probably be tied to the LAC.

Adjust time zone VTY config code (to be moved to libcommon-cs in subsequent commit).

Adjust time zone Ctrl Interface code.

Change-Id: I69848887d92990f3d6f969be80f6ef91f6bdbbe8
diff --git a/openbsc/tests/bsc/bsc_test.c b/openbsc/tests/bsc/bsc_test.c
index 6d41941..7174828 100644
--- a/openbsc/tests/bsc/bsc_test.c
+++ b/openbsc/tests/bsc/bsc_test.c
@@ -147,10 +147,10 @@
 		struct msgb *msg = msgb_alloc(4096, "test-message");
 		int is_set = 0;
 
-		bts->tz.hr = get_int(test_def->params, test_def->n_params, "tz_hr", 0, &is_set);
-		bts->tz.mn = get_int(test_def->params, test_def->n_params, "tz_mn", 0, &is_set);
-		bts->tz.dst = get_int(test_def->params, test_def->n_params, "tz_dst", 0, &is_set);
-		bts->tz.override = 1;
+		net->tz.hr = get_int(test_def->params, test_def->n_params, "tz_hr", 0, &is_set);
+		net->tz.mn = get_int(test_def->params, test_def->n_params, "tz_mn", 0, &is_set);
+		net->tz.dst = get_int(test_def->params, test_def->n_params, "tz_dst", 0, &is_set);
+		net->tz.override = 1;
 
 		printf("Going to test item: %d\n", i);
 		msg->l3h = msgb_put(msg, test_def->length);