st/dri: ask the driver to update its internal copies on reimport

st/dri: ask the driver to update its internal copies on reimport

For imported buffers that can't be used directly as a source to the
texture samplers, the pipe driver might need to create an internal
copy, for example in a different tiling layout. When buffers are
reimported they may contain new image data, so the driver internal
copies need to be recreated.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>