ASoC: ak4458: rstn_control - return a non-zero on error only

snd_soc_component_update_bits() may return 1 if operation
was successful and the value of the register changed.
Return a non-zero in ak4458_rstn_control for an error only.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Signed-off-by: Viorel Suman <viorel.suman@nxp.com>
Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>