firewire: sbp2: remove superfluous blk_queue_max_segment_size() call

The SCSI framework automatically initializes the block queue's segment
size with the DMA device's segment size.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>