nvme-rdma: Allow DELETING state change failure in error_recovery

While error recovery is ongoing, it is OK to move
ctrl to DELETING state (from concurrent delete_work).
Thus we don't need a warning for that case.

Signed-off-by: Nitzan Carmi <nitzanc@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>