[MCJIT] Remove the local symbol table from RuntimeDlyd - it's not needed.

All symbols have to be stored in the global symbol to enable
cross-rtdyld-instance linking, so the local symbol table content is
redundant.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222867 91177308-0d34-0410-b5e6-96231b3b80d8