[PATCH 5/7] serial: clps711x: fix IS_ERR_VALUE usage

[Al Viro]

On Mon, Feb 15, 2016 at 03:35:23PM +0100, Andrzej Hajda wrote:
> IS_ERR_VALUE macro should be used only with unsigned long type.
> For signed types comparison 'ret < 0' should be used.

ACK