Set coding in mncc_set_cause()

GSM 04.08 10.5.4.11

The Release indication needs to have the Coding Standard set.

For phones that would display a message on screen, such as
"Number not in use", if the coding standard is not defined,
the display may show "Error in Connection"

Change-Id: Ib28b62a41d433e231cff5910d19455296b284df6
diff --git a/tests/msc_vlr/msc_vlr_test_call.c b/tests/msc_vlr/msc_vlr_test_call.c
index 6805f1a..065af25 100644
--- a/tests/msc_vlr/msc_vlr_test_call.c
+++ b/tests/msc_vlr/msc_vlr_test_call.c
@@ -401,7 +401,7 @@
 	 * this only worked synchronously, i.e. only with internal MNCC. Instead of mimicking that, we need a proper
 	 * async solution that also works with a PBX. */
 	cc_to_mncc_expect_tx("", MNCC_REL_CNF);
-	dtap_expect_tx("032d080281af"); /* CC: Release */
+	dtap_expect_tx("032d0802e1af"); /* CC: Release */
 	expect_iu_release();
 	msc_a_release_cn(msub_msc_a(g_msub));
 	OSMO_ASSERT(dtap_tx_confirmed);