svn commit: r317755 - head/sbin/ifconfig

[Ngie Cooper]

> On May 3, 2017, at 10:21, Alan Somers <asomers at FreeBSD.org> wrote:
> 
> Author: asomers
> Date: Wed May  3 17:21:01 2017
> New Revision: 317755
> URL: https://svnweb.freebsd.org/changeset/base/317755
> 
> Log:
>  Various Coverity fixes in ifconfig(8)

...

>  * Mark usage() as _Noreturn (1305806, 1305750)

...

> -static    void usage(void);
> +static    void usage(void) _Noreturn;

Hi Alan,
    Please use __dead2 instead to be consistent with legacy use of similar gcc attributes.
Thanks,
-Ngie