drm/amd/display: Allow dirty rects to be sent to dmub when abm is active

[WHY]
It's beneficial for ABM to know when new frame data are available.

[HOW]
Add new condition to allow dirty rects to be sent to DMUB when ABM is
active. ABM will use this as a signal that a new frame has arrived.

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Anthony Koo <anthony.koo@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Josip Pavic <josip.pavic@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>