Docs: add gmake syntax to autoconf script #15071

Environment: FreeBSD 11.2

Running the autoconf script ./configure without MAKE=gmake results in the following error:

"config.status: error: Something went wrong bootstrapping makefile fragments for automatic dependency tracking. Try re-running configure with the '--disable-dependency-tracking' option to at least be able to build the package (albeit without support for automatic dependency tracking). See `config.log' for more details"

Defining MAKE as gmake resolves the error.

Related to #14404. The same configure suggestions was also made there.

There I was hoping that this would be solved upstream so we didn't have to make a documentation change for it (as it seems to be unrelated to anything we do), but if this problem keeps sticking around then ACK from me.

Concept ACK. I agree that having to add this is a bit messy, given it's for automake 1.16+.

If we are going to add it, probably worth adding to the OpenBSD, and likely NetBSD docs as well.

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #15416 (doc: update FreeBSD build guide for 12.0 by fanquake)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

<!--cf906140f33d8803c4a75a2196329ecb-->Needs rebase

Going to close this for now. Any discussion/suggestions etc should continue in #14404, I think we'd rather figure out the root cause of this problem before adding anything to the docs.