[PATCH 0/6] MR7605: PDB rewrite #3

[eric pouech (＠epo)]

This serie (PDB rewrite #3) mostly handles the debug information
needed to support C++ enum underlying integral type.
- it generalizes the use of VARIANT to gather enum values,
- to make things simple, in PDB, the type of variant used has nothing
  to do with the size of the C++ integral type, but is the smallest
  size to hold the considered enum value,
- adapt the dwarf backend to behave the same way as the PDB one,
- adapt debugger to support up to 8-bytes variant types.