drm/msm/dsi: correct byte intf clock rate for 14nm DSI PHY

According to the vendor kernel, byte intf clock rate should be a half of
the byte clock only when DSI PHY version is above 2.0 (in other words,
10nm PHYs and later) and only if PHY is used in D-PHY mode. Currently
MSM DSI code handles only the second part of the clause (C-PHY vs
D-PHY), skipping DSI PHY version check, which causes issues on some of
14nm DSI PHY platforms (e.g. qcm2290).

Move divisor selection to DSI PHY code, pass selected divisor through
shared timings and set byte intf clock rate accordingly.

Cc: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Tested-by: Konrad Dybcio <konrad.dybcio@linaro.org> # SM6115P J606F
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/519006/
Link: https://lore.kernel.org/r/20230118130027.2345719-1-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>