drm/amd/display: Fix USBC link creation

[Description]

Add USBC connector ID to align with new VBIOS parsing.

Add seperate DCN321 link encoder due to different PHY version affecting
DP ALT related registers.

Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Acked-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>