Understand absolute base addresses in ProcessGDBRemote::GetLoadedModuleList.

Summary:
This is useful when dealing with Windows remote that use only the
qXfer:libraries command which returns absolute base addresses, as
opposed to qXfer:libraries-svr4 which returns relative offsets for
module bases.

Reviewers: clayborg, zturner, ADodds

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D12204

llvm-svn: 245625