gpu: ipu-v3: image-convert: disable double buffering if necessary

Double-buffering only works if tile sizes are the same and the resizing
coefficient does not change between tiles, even for non-planar formats.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Steve Longerbeam <slongerbeam@gmail.com>
Tested-by: Steve Longerbeam <slongerbeam@gmail.com>