mount: check bondaries in mount_resolve_path

The current code think that /vz/lxc/centos-6-x86_64-root is
in /vz/lxc/centos-6-x86_64.

If the path is not equal to mountpoint, we need to check, that
path contains a slash after mountpoint.

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
libcriu: Add criu_set_root to the interface.

This function implements the --root command line option in libcriu.

Signed-off-by: Deyan Doychev <deyandoichev@gmail.com>
Reviewed-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>