usb: gadget: f_uac1: fixing inconsistent indenting

Fixing inconsistent indenting identified by kernel test
robot.
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Acked-By: Felipe Balbi <balbi@kernel.org>
Link: https://lore.kernel.org/r/20210817100555.4437-1-pavel.hofman@ivitera.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>