target: Fix exception path pr_reg put regression for PR RELEASE

Fix a regression bug in core_scsi3_emulate_pro_release() where
should still be getting released via core_scsi3_put_pr_reg() during
No persistent reservation, with returing GOOD status.

Use goto statement here to follow converted code from hch.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>