[SymbolFilePDB] Add support for CVR pointer type qualifier

Summary:
- Complete element type of PDBSymbolTypeArray.

- Add a test to check types of multi-dimensional array and pointers with CVR.

Reviewers: zturner, rnk, lldb-commits

Reviewed By: zturner

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44167

llvm-svn: 326859