drm/msm/mdss: Add a TODO for better managing the MDSS clock power state

drm/msm/mdss: Add a TODO for better managing the MDSS clock power state

There's a small window where the MDP clock could be set to a high rate
(say, from the bootloader) without a corresponding RPM(H)PD vote to
back it up. This is normally not an issue, but could be, if rmmod fails
to shut down the display driver cleanly, and the module is inserted
again, or when the providers' .sync_state has timed out.

Mark a TODO to fix it one day. Linking the relevant discussion below.

Link: https://lore.kernel.org/linux-arm-msm/d5c4eed5-bd87-4156-b178-2d78140ec8a9@oss.qualcomm.com/
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/710572/
Link: https://lore.kernel.org/r/20260310-topic-mdss_power_todo-v1-1-59457b8b7486@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>