drm/msm/dpu: use hsync/vsync polarity set by the encoder

drm/msm/dpu: use hsync/vsync polarity set by the encoder

Do not override the hsync/vsync polarity passed by the encoder when
setting up intf timings. The same logic was used in both the encoder and
intf code to set the DP and DSI polarities, so those interfaces are not
impacted. However for HDMI, the polarities were overriden to static
values based on the vertical resolution, instead of using the actual
mode polarities.

Signed-off-by: Arnaud Vrac <avrac@freebox.fr>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/532901/
Link: https://lore.kernel.org/r/20230419-dpu-tweaks-v1-3-d1bac46db075@freebox.fr
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>