EAP: fix a memory leak

(cherry picked from commit 20a6fea312)

epan/dissectors/packet-eap.c

@@ -927,6 +927,7 @@ dissect_eap_identity_wlan(tvbuff_t *tvb, packet_info* pinfo, proto_tree* tree, i
     (guint)(strlen(realm_tokens[2]) - strlen("mcc")), mcc);
 end:
   g_strfreev(tokens);
+  g_strfreev(realm_tokens);
 
   return ret;
 }