ASoC: wcd: properly handle cs, mb and pullup modes

When micbias(mb) is enabled, turn off cs(current source) and
pullup. When cs is enabled, turn on pullup only during playback.
Set button threshold according to mb mode for both mb and pullup.

Change-Id: I3f57006f839033c5eb7071176b40f685454d6d78
Signed-off-by: Yeleswarapu Nagaradhesh <nagaradh@codeaurora.org>