cxgbe/t4_tom: bugfixes in stop/restart.
- Remove toepcb from the toep_list on active open failure.
- Purge the wr_list for an L2T entry on an adpater stop.
Fixes: c1c524852f62 cxgbe/t4_tom: Implement uld_stop and uld_restart for ULD_TOM.
Sponsored by: Chelsio Communications
(cherry picked from commit fef0e39f64a1db796ded8777dbee71fc287f6107)