spmi: pmic-arb: Return an error code if sanity check fails

If the test 'if (channel > 5)' is true, then we will return 'err' which
is known to be 0 at this point.
Return -EINVAL instead.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/spmi/spmi-pmic-arb.c

@@ -954,6 +954,7 @@ static int spmi_pmic_arb_probe(struct platform_device *pdev)
 	if (channel > 5) {
 		dev_err(&pdev->dev, "invalid channel (%u) specified.\n",
 			channel);
+		err = -EINVAL;
 		goto err_put_ctrl;
 	}