[Build-common-hackers] Bug#461513: cdbs: requires aclocal.m4 to be present in order to generate it

[Evan Broder]

> Note that the variable is called DEB_AUTO_UPDATE_ACLOCAL, not
> DEB_AUTO_CREATE_ACLOCAL, so the feature works as designed.

Is this actually in any way a useful design? I can't think of any
scenarios where a maintainer would explicitly set
DEB_AUTO_UPDATE_ACLOCAL and not mean for aclocal to get run.

On the other hand, I can think of a couple of cases where aclocal.m4
might not already exist - braindead upstream being the most obvious.
Alternatively, I've had packages where I patched the upstream source to
the point that I needed to run aclocal after patching.

DEB_AUTO_UPDATE_ACLOCAL isn't something that's set automatically, or
accidentally. It doesn't make sense to me for CDBS to try and
second-guess the package maintainer like this.

- Evan