drm/amd/display: Added power down on boot for DCN3

[Why]
The change of setting a timer callback on boot for 10 seconds is still
working, just lost power down on boot and power down for DCN3.

[How]
Added power down on boot and power down for DCN3.
Reviewed-by: Anthony Koo <anthony.koo@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Derek Lai <Derek.Lai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn31/dcn31_init.c

@@ -34,6 +34,7 @@
 static const struct hw_sequencer_funcs dcn31_funcs = {
 	.program_gamut_remap = dcn10_program_gamut_remap,
 	.init_hw = dcn31_init_hw,
+	.power_down_on_boot = dcn10_power_down_on_boot,
 	.apply_ctx_to_hw = dce110_apply_ctx_to_hw,
 	.apply_ctx_for_surface = NULL,
 	.program_front_end_for_ctx = dcn20_program_front_end_for_ctx,
@@ -93,6 +94,7 @@ static const struct hw_sequencer_funcs dcn31_funcs = {
 	.set_flip_control_gsl = dcn20_set_flip_control_gsl,
 	.get_vupdate_offset_from_vsync = dcn10_get_vupdate_offset_from_vsync,
 	.calc_vupdate_position = dcn10_calc_vupdate_position,
+	.power_down = dce110_power_down,
 	.set_backlight_level = dcn21_set_backlight_level,
 	.set_abm_immediate_disable = dcn21_set_abm_immediate_disable,
 	.set_pipe = dcn21_set_pipe,