[PATCH] Dockerfile: Update to latest "focal" tag

[Bin Meng]

On Sat, Sep 11, 2021 at 10:37 PM Tom Rini <trini at konsulko.com> wrote:
>
> Signed-off-by: Tom Rini <trini at konsulko.com>
> ---
>  tools/docker/Dockerfile | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>