tcmu: Add a missing unlock on an error path

We added a new error path here but we forgot to drop the lock first
before returning.

Fixes: 0d44374c1aae ("tcmu: fix double se_cmd completion")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
1 file changed