Fix null dereference if address is NULL.



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@201026 91177308-0d34-0410-b5e6-96231b3b80d8
hostname is guarantee to never be null in this branch.



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@201027 91177308-0d34-0410-b5e6-96231b3b80d8