[PATCH] ALSA: usb-audio: fix incorrect clock source setting

[chihhao.chen at mediatek.com]

From: chihhao chen <chihhao.chen at mediatek.com>

Hi Geraldo Nascimento,

For echo test, it means we use this earphone to receive and play sounds at the same time.
We found in this case serious noise problem happens.

Log as follows with your patch
<6>[  175.960387][T401365] __uac_clock_find_source: Clock Selector 0xc has pin 2 selected
<6>[  175.966980][T401365] __uac_clock_find_source: Clock Selector 0xb has pin 2 selected
<6>[  176.026251][T400354] __uac_clock_find_source: Clock Selector 0xc has pin 1 selected
<6>[  176.032406][T400354] __uac_clock_find_source: Clock Selector 0xb has pin 1 selected

There is no noise and I think this should be a firmware bug.

Thanks
Chihhao