usb: gadget: audio: Add HS/SS bInterval params for UAC2

Allow configuring the existing f_uac2 configfs bInterval params through
parameters of the gaudio module.

Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Link: https://lore.kernel.org/r/20220127114331.41367-3-pavel.hofman@ivitera.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>