media: platform: rzg2l-cru: rzg2l-csi2: Switch to RUNTIME_PM_OPS()

Replace the old SET_RUNTIME_PM_OPS() helpers with its modern alternative
RUNTIME_PM_OPS(). The usage of pm_ptr and RUNTIME_PM_OPS() allows the
compiler to see where it's used but still drop the dead code. After this
we can get rid of the unnecessary '__maybe_unused' annotations on PM
functions.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Link: https://lore.kernel.org/r/20240213181233.242316-2-biju.das.jz@bp.renesas.com


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