ceph: increment change_attribute on local changes

We don't set SB_I_VERSION on ceph since we need to manage it ourselves,
so we must increment it whenever we update the file times.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>