libevdev: bump version to 1.4.6
Update version and hash (see [1] for details).
[1] http://lists.freedesktop.org/archives/input-tools/2016-January/001240.html
Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>