drm/amd/display: Only blank DCN when we have set_blank implementation

Also rename timing_generator to optc

Signed-off-by: Yue Hin Lau <[email protected]>
Reviewed-by: Eric Bernstein <[email protected]>
Acked-by: Harry Wentland <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
7 files changed