ASoC: wcd9335: Update gain settings for speaker path

Provide an API from wcd9335 codec to update gain settings
for speaker path. Change updates speaker gain offset
during device path bringup.

Change-Id: I0a89538436a64fc4f5efa2fa496e4f35ac636fde
Signed-off-by: Sudheer Papothi <spapothi@codeaurora.org>