Expose the RTDyldMemoryManager through the C API. This allows clients of

Expose the RTDyldMemoryManager through the C API. This allows clients of
the C API to provide their own way of allocating JIT memory (both code
and data) and finalizing memory permissions (page protections, cache
flush).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182448 91177308-0d34-0410-b5e6-96231b3b80d8