Upgrade autogen.sh on PostGIS 2.4, 2.5, 3.0
|Reported by:||robe||Owned by:||robe|
It seems many with autoconf > 2.69 are struggling to compile PostGIS 2.4 and 2.5 and possibly 3.0 chains.
So I think we should backport some of the changes we made in 3.1 to those.
We can mark as a breaking change if needed. My desktop autoconf running 2.69 works fine with 3.1 and 3.2 and that has been out for a while.