dmaengine: ptdma: Remove unused pointer dma_cmd_cache

The pointer 'struct kmem_cache *dma_cmd_cache' was introduced in commit
'b0b4a6b10577 ("dmaengine: ptdma: register PTDMA controller as a DMA
resource")' but it was never used.

Signed-off-by: Eder Zulian <[e-mail]>
Reviewed-by: Nathan Lynch <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/amd/ptdma/ptdma-dmaengine.c

···
 	desc_cache_name = devm_kasprintf(pt->dev, GFP_KERNEL,
 					 "%s-dmaengine-desc-cache",
 					 dev_name(pt->dev));
-	if (!desc_cache_name) {
-		ret = -ENOMEM;
-		goto err_cache;
-	}
+	if (!desc_cache_name)
+		return -ENOMEM;
 
 	pt->dma_desc_cache = kmem_cache_create(desc_cache_name,
 					       sizeof(struct pt_dma_desc), 0,
 					       SLAB_HWCACHE_ALIGN, NULL);
-	if (!pt->dma_desc_cache) {
-		ret = -ENOMEM;
-		goto err_cache;
-	}
+	if (!pt->dma_desc_cache)
+		return -ENOMEM;
 
 	dma_dev->dev = pt->dev;
 	dma_dev->src_addr_widths = DMA_SLAVE_BUSWIDTH_64_BYTES;
···
 err_reg:
 	kmem_cache_destroy(pt->dma_desc_cache);
 
-err_cache:
-	kmem_cache_destroy(pt->dma_cmd_cache);
-
 	return ret;
 }
 EXPORT_SYMBOL_GPL(pt_dmaengine_register);
···
 	dma_async_device_unregister(dma_dev);
 
 	kmem_cache_destroy(pt->dma_desc_cache);
-	kmem_cache_destroy(pt->dma_cmd_cache);
 }

drivers/dma/amd/ptdma/ptdma.h

···
 	/* Support for the DMA Engine capabilities */
 	struct dma_device dma_dev;
 	struct pt_dma_chan *pt_dma_chan;
-	struct kmem_cache *dma_cmd_cache;
 	struct kmem_cache *dma_desc_cache;
 
 	wait_queue_head_t lsb_queue;