[amlogic-display][dsi][clock] Do not use the hardcoded PLL / DSI clock
ratio for LCD panels.

Some LCD panel vendors provided hardcoded PLL / DSI clock ratios
for their LCD panels, while some used automatically calculated
clock ratios.

Since the calculated clock ratios always match the hardcoded values,
this change removes all the hardcoded values and make all displays
to use the automatically calculated values.

This change also adds a test to verify that the calculated clock
ratio matches the original hardcoded values for the affected display
panels.

Test: added PllTimingHdmiPllClockRatioCalculatedCorrectly to clock-test
Test: core.astro, core.nelson and core.sherlock booted (using the
      affected panels)
Change-Id: Ie2c4721b14a92977ef31dd2951dc4cac207cb60e
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/970959
Reviewed-by: Victor Costan <costan@google.com>
Commit-Queue: Yilong Li <liyl@google.com>
2 files changed