Remove the Ada bindings which are unmaintained and unused. The project which

Remove the Ada bindings which are unmaintained and unused.  The project which
was the main putative user of the binding is actually maintaining its own
different binding, see http://git.ada.cx/cgi-bin/cgit.cgi/draco.git/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113960 91177308-0d34-0410-b5e6-96231b3b80d8