drm/msm/mdp5: drop workarounds specific to MDP5 1.0

drm/msm/mdp5: drop workarounds specific to MDP5 1.0

With support for MSM8974v1 being removed from the driver, there is no
need to keep workarounds specific to that particular MDP5 revision. Drop
them, slightly simplifying the logic.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/713918/
Link: https://lore.kernel.org/r/20260325-mdp5-further-drop-mdp1-0-v1-1-5ccee47fd1aa@oss.qualcomm.com