dmaengine: mic_x100_dma: use the new helper to simplify the code

Use dmaenginem_async_device_register() to simplify the code:
    remove the mic_dma_unregister_dma_device()
Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/mic_x100_dma.c

@@ -470,11 +470,6 @@ static void mic_dma_chan_destroy(struct mic_dma_chan *ch)
 	mic_dma_chan_mask_intr(ch);
 }
 
-static void mic_dma_unregister_dma_device(struct mic_dma_device *mic_dma_dev)
-{
-	dma_async_device_unregister(&mic_dma_dev->dma_dev);
-}
-
 static int mic_dma_setup_irq(struct mic_dma_chan *ch)
 {
 	ch->cookie =
@@ -630,7 +625,7 @@ static int mic_dma_register_dma_device(struct mic_dma_device *mic_dma_dev,
 		list_add_tail(&mic_dma_dev->mic_ch[i].api_ch.device_node,
 			      &mic_dma_dev->dma_dev.channels);
 	}
-	return dma_async_device_register(&mic_dma_dev->dma_dev);
+	return dmaenginem_async_device_register(&mic_dma_dev->dma_dev);
 }
 
 /*
@@ -678,7 +673,6 @@ static struct mic_dma_device *mic_dma_dev_reg(struct mbus_device *mbdev,
 
 static void mic_dma_dev_unreg(struct mic_dma_device *mic_dma_dev)
 {
-	mic_dma_unregister_dma_device(mic_dma_dev);
 	mic_dma_uninit(mic_dma_dev);
 	kfree(mic_dma_dev);
 }