ovl: Put upperdentry if ovl_check_origin() fails

If ovl_check_origin() fails, we should put upperdentry. We have a reference
on it by now. So goto out_put_upper instead of out.

Fixes: a9d01957 ("ovl: lookup non-dir copy-up-origin by file handle")
Cc: <stable@vger.kernel.org> #4.12
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>