bsc: Fix TC_paging_resp_unsol

TC_paging_resp_unsol spent some time in gerrit before being merged. As a
result, other commits were merged in between the test was submitted (tested)
and merged. As a result, commit a5302c8151d1da2e43ed52efc0544d70bffab911
was merged while this test was still in gerrit and thus was not updated
accordingly.
Similar stuff happened with the osmo-bsc commit fixing the scenario this
test was showcasing: The osmo-bsc patch (77cd1129931928d2a6e7667d0374feeeed71b0ce)
had merge conflict with other osmo-bsc commits merged in-between,
and was merged even later than the commit introducing this TTCN3 test, so
failures were expected for this test for a while.

Change-Id: I933cba41912640eb7e15be4a27bda5b4dd489962
diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index 962d6c6..81cf23e 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -1519,7 +1519,7 @@
 	f_ipa_tx(0, ts_RSL_EST_IND(dt.rsl_chan_nr, valueof(ts_RslLinkID_DCCH(0)), enc_PDU_ML3_MS_NW(l3)));
 
 	/* expect BSC to disable the channel */
-	f_expect_chan_rel(0, dt.rsl_chan_nr);
+	f_expect_chan_rel(0, dt.rsl_chan_nr, expect_rll_rel_req := false);
 	setverdict(pass);
 
 }