usb: gadget: uvc: fix try format returns on uncompressed formats

When setting uncompressed formats, the values of bytesperline and
sizeimage can already be determined by using the v4l2_fill_pixfmt helper
function. We change the try_fmt function to use the helper instead.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Link: https://lore.kernel.org/r/20240221-uvc-gadget-uncompressed-v1-1-f55e97287cae@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>