Necessary to give disassembler users (like darwin's otool) a possibility to
dlopen libLTO and still initialize the required LLVM bits. This used to go
through libMCDisassembler but that's a gross layering violation, the MC layer
can't pull in functions from the targets. Adding a function to libLTO is a bit
of a hack but not worse than exposing other disassembler bits from libLTO.
Fixes PR14362.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168545 91177308-0d34-0410-b5e6-96231b3b80d8
