dmaengine: ste_dma40: use dmaenginem_async_device_register to simplify the code

Use dmaenginem_async_device_register to simplify the code:
	remove dma_async_device_unregister.
	remove label unregister_slave, unregister_memcpy
Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/ste_dma40.c

@@ -2839,7 +2839,7 @@ static int __init d40_dmaengine_init(struct d40_base *base,
 
 	d40_ops_init(base, &base->dma_slave);
 
-	err = dma_async_device_register(&base->dma_slave);
+	err = dmaenginem_async_device_register(&base->dma_slave);
 
 	if (err) {
 		d40_err(base->dev, "Failed to register slave channels\n");
@@ -2854,12 +2854,12 @@ static int __init d40_dmaengine_init(struct d40_base *base,
 
 	d40_ops_init(base, &base->dma_memcpy);
 
-	err = dma_async_device_register(&base->dma_memcpy);
+	err = dmaenginem_async_device_register(&base->dma_memcpy);
 
 	if (err) {
 		d40_err(base->dev,
 			"Failed to register memcpy only channels\n");
-		goto unregister_slave;
+		goto exit;
 	}
 
 	d40_chan_init(base, &base->dma_both, base->phy_chans,
@@ -2871,18 +2871,14 @@ static int __init d40_dmaengine_init(struct d40_base *base,
 	dma_cap_set(DMA_CYCLIC, base->dma_slave.cap_mask);
 
 	d40_ops_init(base, &base->dma_both);
-	err = dma_async_device_register(&base->dma_both);
+	err = dmaenginem_async_device_register(&base->dma_both);
 
 	if (err) {
 		d40_err(base->dev,
 			"Failed to register logical and physical capable channels\n");
-		goto unregister_memcpy;
+		goto exit;
 	}
 	return 0;
- unregister_memcpy:
-	dma_async_device_unregister(&base->dma_memcpy);
- unregister_slave:
-	dma_async_device_unregister(&base->dma_slave);
  exit:
 	return err;
 }