PD#150879: if continuous-clock is configed, the audio clock don't
gate off when there is audio stream. Also, this commit could simply
set the same MPLL source to make PDM-in and TDM-out work synchronously.
Change-Id: Iac488b4d4813f758f0bc1ebd8bb5f35f9a8dfff1
Signed-off-by: Shuai Li <shuai.li@amlogic.com>