usb: f_uac2: Add support for UAC2 function

Add support for the UAC2 function with the configfs
framework.
Also fix the audio quality issues by increasing the
number of USB_XFERS.

Change-Id: Ie94aee43dd52b0b711778420e485af72730dd28b
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
2 files changed