drm/amd/display: Fix DP Compliance tests 4.3.2.1 and 4.3.2.2

[Why]
Test expects that we also read HPD_IRQ_VECTOR when checking for
symbol loss as well lane status.

[How]
Read bytes 0x200-0x205 instead of just 0x202-0x205

Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Eryk Brol <eryk.brol@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>