EDAC, mv64x60: Fix an error handling path

We should not call edac_mc_del_mc() if a corresponding call to
edac_mc_add_mc() has not been performed yet.

So here, we should go to err instead of err2 to branch at the right
place of the error handling path.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20180107205400.14068-1-christophe.jaillet@wanadoo.frSigned-off-by: Borislav Petkov <bp@suse.de>

drivers/edac/mv64x60_edac.c

@@ -758,7 +758,7 @@ static int mv64x60_mc_err_probe(struct platform_device *pdev)
 		/* Non-ECC RAM? */
 		printk(KERN_WARNING "%s: No ECC DIMMs discovered\n", __func__);
 		res = -ENODEV;
-		goto err2;
+		goto err;
 	}
 
 	edac_dbg(3, "init mci\n");