drm/amd/display: Disable boot optimizations if ILR optimzation is required

[Why]
VBIOS currently sets the max link rate found in eDP 1.4 SUPPORTED_LINK_RATES table
If eDP fastboot optimizations are enabled, the link rate remains at max after init

[How]
Determine optimal link rate during boot, disable seamless boot
and eDP fastboot optimizations if link rate optimization is required

Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Acked-by: Bindu Ramamurthy <bindur12@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>