sgsn: fix TC_attach_check_complete_resend

TC_attach_check_complete_resend tests if the SGSN sends out the SGSN
Attach Accept multiple times. If the MS disappear,
there is no need for a ATTACH REJECT.

Change-Id: I3fa5c100b8389e184acf1e71e2792e5474c22dec
diff --git a/sgsn/SGSN_Tests.ttcn b/sgsn/SGSN_Tests.ttcn
index 66319b5..8094866 100644
--- a/sgsn/SGSN_Tests.ttcn
+++ b/sgsn/SGSN_Tests.ttcn
@@ -1821,13 +1821,16 @@
 	f_send_l3_gmm_llc(ts_GMM_ATTACH_REQ(f_mi_get_lv(), f_random_RAI(), true, false, omit, omit));
 	f_gmm_auth();
 
+	timer T := 10.0;
+	T.start;
 	alt {
-		[] BSSGP[0].receive(tr_BD_L3_MT(tr_GMM_ATTACH_REJECT(?))) {
+		[] T.timeout {
 			/* break */
 		}
 		[] BSSGP[0].receive(tr_BD_L3_MT(tr_GMM_ATTACH_ACCEPT(*, *, *))) {
 			/* ignore */
 			count_req := count_req + 1;
+			T.start;
 			repeat;
 		}
 	}