target: tcm_loop: Delete an unnecessary return statement in tcm_loop_submission_work()

The script "checkpatch.pl" pointed information out like the following.

WARNING: void function return statements are not generally useful

Thus remove such a statement in the affected function.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/loopback/tcm_loop.c

@@ -166,7 +166,6 @@ static void tcm_loop_submission_work(struct work_struct *work)
 out_done:
 	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 	sc->scsi_done(sc);
-	return;
 }
 
 /*