drm/msm/dp: change clock related programming for YUV420 over DP

Change all relevant DP controller related programming for YUV420 cases.
Namely, change the pixel clock math to consider YUV420 and modify the
MVID programming to consider YUV420.

Changes in v2:
	- Move configuration control programming to a different commit
	- Slight code simplification
	- Add VSC SDP check when doing mode_pclk_khz division in
	  dp_bridge_mode_valid

Signed-off-by: Paloma Arellano <quic_parellan@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/579640/
Link: https://lore.kernel.org/r/20240222194025.25329-12-quic_parellan@quicinc.com


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>