[RESEND PATCH v4 2/6] libsas: shut down the PHY if events reached the threshold

If the PHY burst too many events, we will alloc a lot of events for the worker. This may leads to memory exhaustion. Dan Williams suggested to shut down the PHY if the events reached the threshold, because in this case the PHY may have gone into some erroneous state. Users can re-enable the PHY

[RESEND PATCH v4 2/6] libsas: shut down the PHY if events reached the threshold

If the PHY burst too many events, we will alloc a lot of events for the worker. This may leads to memory exhaustion. Dan Williams suggested to shut down the PHY if the events reached the threshold, because in this case the PHY may have gone into some erroneous state. Users can re-enable the PHY