[llvm-pdbdump] Dump File / Line Info to YAML.

We were already parsing and dumping this to the human readable
format, but not to the YAML format.  This does so, in preparation
for reading it in and reconstructing the line information from
YAML.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301357 91177308-0d34-0410-b5e6-96231b3b80d8
12 files changed