drm/amd/display: Allow MPO on Raven

Signed-off-by: Leon Elazar <leon.elazar@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c

@@ -1292,6 +1292,8 @@ static bool construct(
 	dc->public.caps.i2c_speed_in_khz = 100;
 	dc->public.caps.max_cursor_size = 256;
 
+	dc->public.caps.max_slave_planes = 1;
+
 	if (dc->ctx->dce_environment == DCE_ENV_PRODUCTION_DRV)
 		dc->public.debug = debug_defaults_drv;
 	else