Patch by Ramkumar Ramachandra <artagnon@gmail.com>.
Also remove Llvm_executionengine.get_pointer_to_global, as it
is actually deprecated and didn't appear in a stable release.
llvm-svn: 224801
ocamlc and ocamlopt expose a distinct set of buildsystem bugs, e.g.
only ocamlc would detect -custom or -dllib-related bugs, and as all
buildbots will have ocamlopt, these bugs will stay hidden.
This change should add no more than 30 seconds of testing time.
llvm-svn: 221137