drm/amd/display: Fix accessing freed memory

Signed-off-by: Corbin McElhanney <corbin.mcelhanney@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/core/dc.c

@@ -1714,8 +1714,11 @@ void dc_update_planes_and_stream(struct dc *dc,
 	}
 
 	if (core_dc->current_context != context) {
-		dc_release_validate_context(core_dc->current_context);
+		struct validate_context *old = core_dc->current_context;
+
 		core_dc->current_context = context;
+		dc_release_validate_context(old);
+
 	}
 	return;