ASoC: wcd938x: Update the soundwire clock rate based on the tx paths

Update the soundwire clock rate based on the number of TX paths enable
to avoid noise issue.

Change-Id: I8c73bfd73751d4b79de30f3347081929501a877e
Signed-off-by: Sudheer Papothi <spapothi@codeaurora.org>