drm/panfrost: Add GPU_PM_RT support for RZ/G3E SoC

drm/panfrost: Add GPU_PM_RT support for RZ/G3E SoC

RZ/G3E SoC is embedded with Mali-G52 GPU system. The system hangs after
STR in the following condition:

STR -> Wakeup from STR -> Unload panfrost using 'modprobe -r panfrost'.

Fix this issue by asserting/deasserting the reset during suspend/resume.
Rename the variable allwinner_h616_data->default_pm_rt_data for data
reuse and make it as generic GPU PM runtime data.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251203125104.67596-1-biju.das.jz@bp.renesas.com
Signed-off-by: Adrian Larumbe <adrianml@alumnos.upm.es>