usb: gadget: uvc: add v4l2 try_format api call

This patch adds the uvc_v4l2_try_format api call to validate
the setting of v4l2_format. It will fallback to the nearest
allowed framesize.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Link: https://lore.kernel.org/r/20220909221335.15033-5-m.grzeschik@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>