Block the SCSI host while reconnecting instead of representing the
reconnection activity as a distinct SRP target state.  This allows us
to eliminate the target state SRP_TARGET_CONNECTING.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Acked-by: NDavid Dillow <dillowda@ornl.gov>
Signed-off-by: NRoland Dreier <roland@purestorage.com>