ASoC: wcd9xxx: Correct RCO enable and disable sequence

Correct RCO enable and disable sequence. Add bandgap
enable before setting RCO and disable bandgap after RCO
is turned off. Also, codec internal clock gating for master
clock cannot be disabled in order to avoid codec digital state
machine from going to bad state which may result into intermittent
audio loss.

Change-Id: Ife4994e4ca5abd6e69b85fdb1a632441b682969a
Signed-off-by: Phani Kumar Uppalapati <phaniu@codeaurora.org>