[llvm] [ocaml] Support linking against dylib
[llvm] [ocaml] Support linking against dylib

Support linking OCaml modules against LLVM dylib when requested,
rather than against static libs that might not be installed at all.

Differential Revision: https://reviews.llvm.org/D68452

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@374556 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm