net: emaclite: Use resource_size

Use the resource_size function instead of manually calculating the
resource size.  This reduces the chance of introducing off-by-one
errors.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/xilinx_emaclite.c

@@ -1171,7 +1171,7 @@ static int __devinit xemaclite_of_probe(struct of_device *ofdev,
 	}
 
 	/* Get the virtual base address for the device */
-	lp->base_addr = ioremap(r_mem.start, r_mem.end - r_mem.start + 1);
+	lp->base_addr = ioremap(r_mem.start, resource_size(&r_mem));
 	if (NULL == lp->base_addr) {
 		dev_err(dev, "EmacLite: Could not allocate iomem\n");
 		rc = -EIO;
@@ -1224,7 +1224,7 @@ static int __devinit xemaclite_of_probe(struct of_device *ofdev,
 	return 0;
 
 error1:
-	release_mem_region(ndev->mem_start, r_mem.end - r_mem.start + 1);
+	release_mem_region(ndev->mem_start, resource_size(&r_mem));
 
 error2:
 	xemaclite_remove_ndev(ndev);