Add missing refcounting for flush_batch errors

src/osd/osd_primary_write.cpp

@@ -7,6 +7,12 @@
 bool osd_t::check_write_queue(osd_op_t *cur_op, pg_t & pg)
 {
     osd_primary_op_data_t *op_data = cur_op->op_data;
+    // First check if PG is not active anymore
+    if (!(pg.state & PG_ACTIVE))
+    {
+        pg_cancel_write_queue(pg, cur_op, op_data->oid, -EPIPE);
+        return false;
+    }
     // Check if actions are pending for this object
     auto act_it = pg.flush_actions.lower_bound((obj_piece_id_t){
         .oid = op_data->oid,