media: nxp: imx8-isi: Move i.MX8 gasket configuration to an ops structure

The i.MX93 includes an ISI instance compatible with the imx8-isi
driver, but with a different gasket. To prepare for this, make the
gasket configuration modular by moving the code to an ops structure.

Signed-off-by: Guoniu.zhou <guoniu.zhou@nxp.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>