The cgo problem was that it wants dwarf2 which doesn't support direct
constant encoding of the location. So let's add support for dwarf2
encoding (using a location expression) of data member locations.
This reverts commit r198385.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198389 91177308-0d34-0410-b5e6-96231b3b80d8