drm/amdgpu: Fix memory leak in hpd_rx_irq_create_workqueue()

If construction of the array of work queues to handle hpd_rx_irq offload
work fails, we need to unwind. Destroy all the created workqueues and
the allocated memory for the hpd_rx_irq_offload_work_queue struct array.

Fixes: 8e794421 ("drm/amd/display: Fork thread to offload work of hpd_rx_irq")
Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -1296,13 +1296,21 @@ static struct hpd_rx_irq_offload_work_queue *hpd_rx_irq_create_workqueue(struct
 
 		if (hpd_rx_offload_wq[i].wq == NULL) {
 			DRM_ERROR("create amdgpu_dm_hpd_rx_offload_wq fail!");
-			return NULL;
+			goto out_err;
 		}
 
 		spin_lock_init(&hpd_rx_offload_wq[i].offload_lock);
 	}
 
 	return hpd_rx_offload_wq;
+
+out_err:
+	for (i = 0; i < max_caps; i++) {
+		if (hpd_rx_offload_wq[i].wq)
+			destroy_workqueue(hpd_rx_offload_wq[i].wq);
+	}
+	kfree(hpd_rx_offload_wq);
+	return NULL;
 }
 
 struct amdgpu_stutter_quirk {