rfc/patch: user-agent distro-description for debuginfod http traffic

[Frank Ch. Eigler]

Hi -

> Eep. We really should pick up this info during runtime instead of
> during build time. 

That's what I thought at first too.  However, doing it at run time
means doing work - a popen() etc. - over and over or saving in a
locked global.  Since on a normal machine, the distro doesn't change
without elfutils also changing, it's practically a literal.

> We do want a reproducible build. 

Can you give an example?  Bootstrapping a new distro version/arch?

> And this will most likely produce wrong information if the package
> build server is on a different OS or release than the OS/release it
> is producing packages for. uname -sm might be "stable", but probably
> not when cross- compiling.

I wonder if the cross-compiled debuginfod-client case is worth
worrying about.

> But where does lsb_release come from? I don't have that on my
> systems.

BuildRequires: /usr/bin/lsb_release :-) It's a different package on
different distros.  And running at run time would make a Require:
rather than a one-time BuildRequire:.

- FChE