ASoC: omap: Use single hw_params callback in sdp3430 and zoom2

There is no need to use two hw_params callbacks in sdp3430 and zoom2 as
thet are now identical. Use instead the same snd_soc_ops structure and
hw_params callback for both DAI links.

Signed-off-by: Jarkko Nikula <jarkko.nikula@bitmer.com>
Cc: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>