If the internal clock is deadly accurate for the desired mode, that will be used instead
(the accuracy is set to within 1/200th which is well within VESA standards of 1/50th) to
save power.
efikamx changes: for HDMI, try external clock when necessary. For LVDS, don't since there
is some weird clock mess with the binary blob for the LCD panels in the mtl017 driver
which we think is derived from the lack of external clock support in more ancient kernels.
It is fudging the values to both correct some kind of panel EDID bug and also to fix the
potential deviation in clock, but since it's a binary blob it's kind of hard to change.
4fa3f18a58