dmaengine: idxd: add missing percpu ref put on failure

When enqcmds() fails, exit path is missing a percpu_ref_put(). This can
cause failure on shutdown path when the driver is attempting to quiesce the
wq. Add missing percpu_ref_put() call on the error exit path.

Fixes: 93a40a6d ("dmaengine: idxd: add percpu_ref to descriptor submission path")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162456170168.1121236.7240941044089212312.stgit@djiang5-desk3.ch.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/idxd/submit.c

@@ -118,8 +118,10 @@ int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
 		 * device is not accepting descriptor at all.
 		 */
 		rc = enqcmds(portal, desc->hw);
-		if (rc < 0)
+		if (rc < 0) {
+			percpu_ref_put(&wq->wq_active);
 			return rc;
+		}
 	}
 
 	percpu_ref_put(&wq->wq_active);