sfc: Warn if unable to create MTDs

Log an explicit warning if we are unable to create MTDs for a net
device.  Also correct the comment about why mtd_device_register() may
fail; there is no longer an MTD table to fill up.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

drivers/net/ethernet/sfc/efx.c

@@ -2502,9 +2502,14 @@ static int __devinit efx_pci_probe(struct pci_dev *pci_dev,
 
 	netif_dbg(efx, probe, efx->net_dev, "initialisation successful\n");
 
+	/* Try to create MTDs, but allow this to fail */
 	rtnl_lock();
-	efx_mtd_probe(efx); /* allowed to fail */
+	rc = efx_mtd_probe(efx);
 	rtnl_unlock();
+	if (rc)
+		netif_warn(efx, probe, efx->net_dev,
+			   "failed to create MTDs (%d)\n", rc);
+
 	return 0;
 
  fail4:

drivers/net/ethernet/sfc/mtd.c

@@ -280,7 +280,7 @@ fail:
 		--part;
 		efx_mtd_remove_partition(part);
 	}
-	/* mtd_device_register() returns 1 if the MTD table is full */
+	/* Failure is unlikely here, but probably means we're out of memory */
 	return -ENOMEM;
 }