IB/srp: Complete correct SCSI commands on device reset

When flushing out queued commands after a successful device reset,
make sure that SRP completes the right commands, instead of calling
scsi_done on the command passed into the device reset handler over and
over.

Signed-off-by: Ishai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>