[VOL-5486] Fix deprecated versions

Change-Id: I3e03ea246020547ae75fa92ce8cf5cbba7e8f3bb
Signed-off-by: Abhay Kumar <abhay.kumar@radisys.com>
diff --git a/vendor/github.com/jcmturner/gokrb5/v8/client/TGSExchange.go b/vendor/github.com/jcmturner/gokrb5/v8/client/TGSExchange.go
index e4571ce..fd01342 100644
--- a/vendor/github.com/jcmturner/gokrb5/v8/client/TGSExchange.go
+++ b/vendor/github.com/jcmturner/gokrb5/v8/client/TGSExchange.go
@@ -89,7 +89,12 @@
 		return tkt, skey, nil
 	}
 	princ := types.NewPrincipalName(nametype.KRB_NT_PRINCIPAL, spn)
-	realm := cl.Config.ResolveRealm(princ.NameString[len(princ.NameString)-1])
+	realm := cl.spnRealm(princ)
+
+	// if we don't know the SPN's realm, ask the client realm's KDC
+	if realm == "" {
+		realm = cl.Credentials.Realm()
+	}
 
 	tgt, skey, err := cl.sessionTGT(realm)
 	if err != nil {