[OpenMP][libomp] Improve Windows Processor Group handling within topology

The current implementation of Windows Processor Groups has
a separate topology method to handle them. This patch deprecates
that specific method and uses the regular CPUID topology
method by default and inserts the Windows Processor Group objects
in the topology manually.

Notes:
* The preference for processor groups is lowered to a value less than
  socket so that the user will see sockets in the KMP_AFFINITY=verbose
  output instead of processor groups when sockets=processor groups.
* The topology's capacity is modified to handle additional topology layers
  without the need for reallocation.
* If a user asks for a granularity setting that is "above" the processor
  group layer, then the granularity is adjusted "down" to the processor
  group since this is the coarsest layer available for threads.

Differential Revision: https://reviews.llvm.org/D112273