Use dcr_host_t.base in dcr_unmap()

With the base stored in dcr_host_t, there's no need for callers to pass
the dcr_n into dcr_unmap(). In fact this removes the possibility of them
passing the incorrect value, which would then be iounmap()'ed.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/ibm_newemac/mal.c

@@ -627,7 +627,7 @@ static int __devinit mal_probe(struct of_device *ofdev,
  fail2:
 	dma_free_coherent(&ofdev->dev, bd_size, mal->bd_virt, mal->bd_dma);
  fail_unmap:
-	dcr_unmap(mal->dcr_host, dcr_base, 0x100);
+	dcr_unmap(mal->dcr_host, 0x100);
  fail:
 	kfree(mal);