w1: omap_hdq: Free resources on error path

In case of error returned by '_omap_hdq_reset()', free resources as done
elsewhere in this function.

This patch slighly changes the semantic of the code. It now propagates the
error code returned by '_omap_hdq_reset()' instead of returning -EINVAL
unconditionally.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>