[cfe-dev] Cleanup on aisle DebugInfo enums

[Robinson, Paul via cfe-dev]

In r259489, Benny Kramer moved the DebugInfoKind enum into its own
header, include/clang/Driver/DebugInfoKind.h. This was to prevent
Driver from pulling in headers from Frontend.  However, this leaves
the enum in kind of a weird place, I think Basic would be better (and
not re-introduce the problem Benny was solving).

Wondering why the tuning enum didn't cause the same problem, I found
that when I created the Clang enum, I didn't make Driver use it; it's
still using the LLVM version of the enum.  While this is not
technically wrong (you could rearrange the values and it would do no 
harm) it's an inconsistency within Clang.

But, if I make Driver use the tuning enum from Clang's CodeGenOptions,
then we'll have the same problem that prompted r259489 in the first
place--Driver depending on Frontend. Rather than create Yet Another
Header, it would be convenient to put the tuning enum in the same
place as DebugInfoKind, as they are topically related and commonly 
used in the same places.

I propose to do the following:

Patch #1 (totally mechanical)
- move DebugInfoKind.h from Driver to Basic
- rename it to DebugInfoOptions.h
This will take care of all the #include renaming in one go.

Patch #2 (basically mechanical)
- move the DebuggerKind enum from CodeGenOptions.h to DebugInfoOptions.h
- fix up Driver to use this enum instead of the LLVM equivalent.

Or I can do it all at once, the combined patch would still be
reasonable I think.

Sound okay?
--paulr