Fixes LLDB address ranges with gcc 4.8
- Modifies the DWARF parser for DWARF 4 specification of hi_pc as an offset-from-low-pc.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@187125 91177308-0d34-0410-b5e6-96231b3b80d8