target: Remove extra percpu_ref_init

lun->lun_ref is also initialized in core_tpg_post_addlun, so it doesn't
need to be done in core_tpg_setup_virtual_lun0.

(nab: Drop left-over percpu_ref_cancel_init in failure path)

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_tpg.c b/drivers/target/target_core_tpg.c
index f755712..2a573de 100644
--- a/drivers/target/target_core_tpg.c
+++ b/drivers/target/target_core_tpg.c
@@ -656,16 +656,10 @@
 	spin_lock_init(&lun->lun_sep_lock);
 	init_completion(&lun->lun_ref_comp);
 
-	ret = percpu_ref_init(&lun->lun_ref, core_tpg_lun_ref_release);
+	ret = core_tpg_post_addlun(se_tpg, lun, lun_access, dev);
 	if (ret < 0)
 		return ret;
 
-	ret = core_tpg_post_addlun(se_tpg, lun, lun_access, dev);
-	if (ret < 0) {
-		percpu_ref_cancel_init(&lun->lun_ref);
-		return ret;
-	}
-
 	return 0;
 }