Fix TC_ms_reg_enq

In the pooling case it is not clear where the message will be forwarded
to so allow reception on any SGSN.

Change-Id: I6669ed0b49e9f278f16a67dc05ae208884ee535e
Related: OS#4472
diff --git a/gbproxy/GBProxy_Tests.ttcn b/gbproxy/GBProxy_Tests.ttcn
index dd33106..6aa5e0c 100644
--- a/gbproxy/GBProxy_Tests.ttcn
+++ b/gbproxy/GBProxy_Tests.ttcn
@@ -2860,7 +2860,7 @@
 
 private function f_TC_ms_reg_enq(charstring id) runs on BSSGP_ConnHdlr
 {
-	f_pcu2sgsn(ts_BSSGP_MS_REG_ENQ(g_pars.imsi), tr_BSSGP_MS_REG_ENQ(g_pars.imsi), use_sig := true);
+	f_pcu2any_sgsn(ts_BSSGP_MS_REG_ENQ(g_pars.imsi), tr_BSSGP_MS_REG_ENQ(g_pars.imsi), use_sig := true);
 	f_sgsn2pcu(ts_BSSGP_MS_REW_ENQ_RESP(g_pars.imsi, omit), tr_BSSGP_MS_REW_ENQ_RESP(g_pars.imsi, omit), use_sig := true);
 }
 testcase TC_ms_reg_enq() runs on test_CT