drm/amd/display: add monitor patch to add T7 delay

[Why]
Specifically to one panel,
TCON is able to accept active video signal quickly, but
the Source Driver requires 2-3 frames of extra time.

It is a Panel issue since TCON needs to take care of
all Sink requirements including Source Driver. But in
this case it does not.

Customer is asking to add fixed T7 delay as panel
workaround.

[How]
Add monitor specific patch to add T7 delay

Signed-off-by: Anthony Koo <anthony.koo@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>