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 <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/spmi/spmi-pmic-arb.c

···
 	if (channel > 5) {
 		dev_err(&pdev->dev, "invalid channel (%u) specified.\n",
 			channel);
+		err = -EINVAL;
 		goto err_put_ctrl;
 	}