runtime: deprecate runc --criu / -criu-path option

runc option --criu is now ignored (with a warning), and the option will be
removed entirely in a future release. Users who need a non- standard criu
binary should rely on the standard way of looking up binaries in $PATH.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

runtime/v2/runc/manager/manager_linux.go

@@ -261,7 +261,7 @@ func (manager) Stop(ctx context.Context, id string) (shim.StopStatus, error) {
 		root = opts.Root
 	}
 
-	r := process.NewRunc(root, path, ns, runtime, "", false)
+	r := process.NewRunc(root, path, ns, runtime, false)
 	if err := r.Delete(ctx, id, &runcC.DeleteOpts{
 		Force: true,
 	}); err != nil {