Bug/git tag detection in Makefile is wrong

[mmetc]

Describe the bug

The Makefile sets BUILD_VERSION to the last tag I created, even if it has nothing to do with the branch I am on.
The behavior is the same in the firewall bouncer.

To Reproduce

$ git checkout some-branch
$ git tag -a -m blah-blah blah-blah
$ git checkout master
$ git describe --tags `git rev-list --tags --max-count=1`
blah-blah
$ git describe --tags                                    
v1.3.0-28-gead0a06f

Since I prepare freebsd tags on a Linux machine, all my Linux (local) builds have a freebsd tag as well, with a wrong version too.

Expected behavior

I would expect a BUILD_VERSION with a tag that appears in the commit history of the branch I am building.
The BUILD_TAG is correct.