D4820: logtoprocess: sends the canonical command name to the subprocess

[Yuya Nishihara]

> +                    # extract the canonical command from the passed opts.
> +                    # we need to pop it up from the opts else the msg will try
> +                    # being formatted using the passed opts.

Oops, that's probably a bug. IIUC, `**opts` is just ancillary data, and
the `msg[0]` should always be parameterized by `msg[1:]`. That's how blackbox
works.

Can you send a separate patch to fix the issue?