ASoC: wcd9306: add compander support

The compander system on the wcd9306 codec is for enhancing
signal to noise ratio. Compander support is added only for
Rx paths in the codec. Add compander support to achieve
higher audio quality by reducing noise. Add wavegen timings
for companders.

Change-Id: Ic0802e44e9827fd396e8768f7541e7bdec69c7b0
Signed-off-by: Banajit Goswami <bgoswa@codeaurora.org>