drm/amd/display: Refine aux transaction before retrieve caps

drm/amd/display: Refine aux transaction before retrieve caps

[Why]
LTTPR caps will read fail if aux channel is not active.

[How]
1.Perform 600 read upto 10 retry with 1ms delay in between.
2.If fail, return false and trigger another retry detection.
3.If pass, read LTTPR caps in retrieve link caps.

Reviewed-by: Jimmy Kizito <Jimmy.Kizito@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Lewis Huang <Lewis.Huang@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>