The refresh reported by modetest is 60.46Hz, and the actual measurement
is 60.01Hz, which is outside the expected tolerance. Adjust hporch and
pixel clock to fix it. After repair, modetest and actual measurement were
all 60.01Hz.

Modetest refresh = Pixel CLK/ htotal* vtotal, but measurement frame rate
is HS->LP cycle time(Vblanking). Measured frame rate is not only affecte
by Htotal/Vtotal/pixel clock, also affected by Lane-num/PixelBit/LineTime
/DSI CLK. Assume that the DSI controller could not make the mode that we
requested(presumably it's PLL couldn't generate the exact pixel clock?).
If you use a different DSI controller, you may need to readjust these
parameters. Now this panel looks like it's only used by me on the MTK
platform, so let's change this set of parameters.

Fixes: 1bc2ef06 ("drm/panel: Support for Starry-himax83102-j02 TDDI MIPI-DSI panel")
Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231120020109.3216343-1-yangcong5@huaqin.corp-partner.google.com