drm/amd/display: refactor destructive verify link cap sequence

[how]
1. move decide det link training link resource before each link training.
2. move disable link for handling vbios case into set all streams
dpms off for link sequence.
3. extract usbc hotplug workaround into its own wa function.
4. Minor syntax changes to improve code readability.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Acked-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>