Reformat const for readability.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195522 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor DW_AT_ranges handling to use labels for ranges rather than
a non-relocatable number offset.

One fixme to make the ranges as discrete data structures and
have range lists explicitly represented rather than as a list of symbols.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195523 91177308-0d34-0410-b5e6-96231b3b80d8