gsup: indicate CN-Domain in SendAuthInfo Requests

In order for osmo-hlr to be able to 100% guarantee distinct INDs for CS and PS,
set CN-Domain = CS in all SendAuthInfo Requests.

In Milenage auth, it is highly desirable that osmo-hlr guarantees use of
distinct INDs for CS and PS domains.  If an MSC and SGSN attached at the same
time use the same IND bucket to generate Milenage SQN, that collision would
rapidly waste SQNs and load osmo-hlr with requesting new auth tuples on each
CS/PS Complete-Layer3.

So far, osmo-msc did not indicate the CN domain in the GSUP SendAuthInfo
Request, which was neither required nor evaluated. The CN-Domain is only sent
for the UpdateLocation Request that usually follows later.

Related: OS#4318
Change-Id: I22f44068268e62801cadbf6542efaf153423cd65
diff --git a/tests/msc_vlr/msc_vlr_test_call.c b/tests/msc_vlr/msc_vlr_test_call.c
index 339233c..b4e20be 100644
--- a/tests/msc_vlr/msc_vlr_test_call.c
+++ b/tests/msc_vlr/msc_vlr_test_call.c
@@ -53,7 +53,7 @@
 
 	btw("Location Update request causes a GSUP Send Auth Info request to HLR");
 	lu_result_sent = RES_NONE;
-	gsup_expect_tx("080108" "09710000000156f0" VLR_TO_HLR);
+	gsup_expect_tx("080108" "09710000000156f0" CN_DOMAIN VLR_TO_HLR);
 	ms_sends_msg("0508" /* MM LU */
 		     "7" /* ciph key seq: no key available */
 		     "0" /* LU type: normal */
@@ -127,7 +127,7 @@
 	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");
 
 	btw("MS sends SecurityModeControl acceptance, VLR accepts and sends GSUP LU Req to HLR");
-	gsup_expect_tx("04010809710000000156f0280102" VLR_TO_HLR);
+	gsup_expect_tx("04010809710000000156f0" CN_DOMAIN VLR_TO_HLR);
 	ms_sends_security_mode_complete();
 	VERBOSE_ASSERT(gsup_tx_confirmed, == true, "%d");
 	VERBOSE_ASSERT(lu_result_sent, == RES_NONE, "%d");