enable chroot_enforce_chdir by default

This does not appear to break any software, so it might as well be enabled.


git-svn-id: file:///srv/repos/svn-community/svn@112992 9fca08f4-af9d-4005-b8df-a31f2cc04f65
linux-grsec: reword chroot restrictions comment


git-svn-id: file:///srv/repos/svn-community/svn@112993 9fca08f4-af9d-4005-b8df-a31f2cc04f65