Fix recent typo preventing MS from registering

Fixes: 0052051c07af63da98137c9f8e3b3119642eb587
Change-Id: Icbbf7340d78ef709ea00d527036533a14e9c21f9
diff --git a/src/gprs_bssgp_pcu.cpp b/src/gprs_bssgp_pcu.cpp
index 14d1a9d..d008d02 100644
--- a/src/gprs_bssgp_pcu.cpp
+++ b/src/gprs_bssgp_pcu.cpp
@@ -123,7 +123,7 @@
 	{
 		rc = osmo_mobile_identity_decode(&mi_imsi, TLVP_VAL(tp, BSSGP_IE_IMSI), TLVP_LEN(tp, BSSGP_IE_IMSI),
 						 true);
-		if (rc < 0 || mi_imsi.type != GSM_MI_TYPE_TMSI) {
+		if (rc < 0 || mi_imsi.type != GSM_MI_TYPE_IMSI) {
 			LOGP(DBSSGP, LOGL_NOTICE, "Failed to parse IMSI IE (rc=%d)\n", rc);
 			return bssgp_tx_status(BSSGP_CAUSE_COND_IE_ERR, NULL, msg);
 		}