this is required by the new button timeout feature
Signed-off-by: John Crispin <blogic@openwrt.org>

Backport of r46471

git-svn-id: svn://svn.openwrt.org/openwrt/branches/chaos_calmer@46581 3c298f89-4303-0410-b956-a3cf2f4a3e73