net: stmmac: reduce dma ring display code duplication

The code to show extended descriptor is identical to normal one.
Consolidate the code to remove duplication.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Link: https://lore.kernel.org/r/a2a5c5ce9338bdea60ec71d7eeb00fe757281557.1700372381.git.baruch@tkos.co.il
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -6180,29 +6180,23 @@ static struct dentry *stmmac_fs_dir;
 static void sysfs_display_ring(void *head, int size, int extend_desc,
 			       struct seq_file *seq, dma_addr_t dma_phy_addr)
 {
-	int i;
 	struct dma_extended_desc *ep = (struct dma_extended_desc *)head;
 	struct dma_desc *p = (struct dma_desc *)head;
+	unsigned int desc_size;
 	dma_addr_t dma_addr;
+	int i;
 
+	desc_size = extend_desc ? sizeof(*ep) : sizeof(*p);
 	for (i = 0; i < size; i++) {
-		if (extend_desc) {
-			dma_addr = dma_phy_addr + i * sizeof(*ep);
-			seq_printf(seq, "%d [%pad]: 0x%x 0x%x 0x%x 0x%x\n",
-				   i, &dma_addr,
-				   le32_to_cpu(ep->basic.des0),
-				   le32_to_cpu(ep->basic.des1),
-				   le32_to_cpu(ep->basic.des2),
-				   le32_to_cpu(ep->basic.des3));
-			ep++;
-		} else {
-			dma_addr = dma_phy_addr + i * sizeof(*p);
-			seq_printf(seq, "%d [%pad]: 0x%x 0x%x 0x%x 0x%x\n",
-				   i, &dma_addr,
-				   le32_to_cpu(p->des0), le32_to_cpu(p->des1),
-				   le32_to_cpu(p->des2), le32_to_cpu(p->des3));
+		dma_addr = dma_phy_addr + i * desc_size;
+		seq_printf(seq, "%d [%pad]: 0x%x 0x%x 0x%x 0x%x\n",
+				i, &dma_addr,
+				le32_to_cpu(p->des0), le32_to_cpu(p->des1),
+				le32_to_cpu(p->des2), le32_to_cpu(p->des3));
+		if (extend_desc)
+			p = &(++ep)->basic;
+		else
 			p++;
-		}
 	}
 }