This particular text can be seen by running ‘make help-dist’.
There are a couple of goals which are specially useful for the package maintainers: ‘dist’ and ‘distcheck’. The former creates a pristine distribution tarball, and the latter does as the former but additionally performs a lengthy check on the resultant tarball to ensure its soundness. As one would expect, unlike other goals, both of this goals doesn’t accept any suffixes, because there is no sense in partitioning the distribution tarball.