presence: Fix memory leak in DB code

modules/presence/presentity.c

@@ -396,9 +396,11 @@ int delete_presentity_if_dialog_id_exists(presentity_t* presentity, char* dialog
 	if(result == NULL)
 		return -3;
 
-	// No results from query definitely means no dialog exists
-	if (result->n <= 0)
+	/* no results from query definitely means no dialog exists */
+	if (result->n <= 0) {
+		pa_dbf.free_result(pa_db, result);
 		return 0;
+	}
 
 	// Loop the rows returned from the DB
 	for (i=0; i < result->n; i++)