IB/mlx4: Fix incorrect comment

mlx4 hardware does not support external DDR memory.  Moreover, UAR
area (BAR 2) can change depending on FW version.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/net/mlx4/main.c

@@ -736,8 +736,7 @@ static int __mlx4_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
 	}
 
 	/*
-	 * Check for BARs.  We expect 0: 1MB, 2: 8MB, 4: DDR (may not
-	 * be present)
+	 * Check for BARs.  We expect 0: 1MB
 	 */
 	if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
 	    pci_resource_len(pdev, 0) != 1 << 20) {