ASoC: tas2552: Propagate the error code in suspend/resume

tas2552_suspend() and tas2552_resume() currently always return success,
even though they may fail.

Fix this behaviour by always propagating the error code.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>