media: imx-jpeg: Add encoder ops layer for hardware abstraction

media: imx-jpeg: Add encoder ops layer for hardware abstraction

Introduce mxc_jpeg_enc_ops function pointer structure to abstract
encoder configuration differences between hardware versions.

Extract the existing two-phase manual configuration into dedicated
functions (enter_config_mode/exit_config_mode) for v0 hardware.
Add setup_desc callback placeholder for future v1 hardware support
which will use descriptor-based configuration.

Store the extended sequential mode flag in the context to avoid
recalculating it during configuration phases.

No functional change.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Ming Qian <ming.qian@oss.nxp.com>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>