By folding scsi_end_request into its only caller we can significantly clean
up the completion logic. We can use simple goto labels now to only have
a single place to finish or requeue command there instead of the previous
convoluted logic.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de>