How to build dub from source on Raspberry PI 4 , freebsd-OS, having a functional ldc2 compiler

[Richard (Rikki) Andrew Cattermole]

For dmd to specify a version to enable you use ``-version=``, for ldc 
you use ``--d-version=``.

But why is it using ldc2 to compile? Its meant to be using the wrapper 
ldmd2 which swaps the dmd style to ldc2 style.

Also why are you building dub? Does your build of ldc not come with it 
for some reason?