drm/amd/display: Re-enable Vsync Interrupts for Gradual Refresh Ramp

- Make sure Vsync interrupts are disabled in static screen case
  and enabled when not to save power
- Create no_static_for_external_dp debug option

Signed-off-by: Amy Zhang <Amy.Zhang@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/modules/inc/mod_freesync.h

@@ -88,6 +88,7 @@ struct mod_freesync_caps {
 	unsigned int max_refresh_in_micro_hz;
 
 	bool btr_supported;
+	bool no_static_for_external_dp;
 };
 
 struct mod_freesync_params {
@@ -129,6 +130,10 @@ bool mod_freesync_get_user_enable(struct mod_freesync *mod_freesync,
 		const struct dc_stream *stream,
 		struct mod_freesync_user_enable *user_enable);
 
+bool mod_freesync_get_static_ramp_active(struct mod_freesync *mod_freesync,
+		const struct dc_stream *stream,
+		bool *is_ramp_active);
+
 bool mod_freesync_override_min_max(struct mod_freesync *mod_freesync,
 		const struct dc_stream *streams,
 		unsigned int min_refresh,