C++ classes for cpuid and hardware topology

C++ classes for cpuid and hardware topology

Refactored old cpuid into classes for cpuid and hardware
topology detection, and moved SIMD architecture selection
routines to the SIMD module. This will make it possible
to introduce hwloc transparently to get more advanced
topology information from the hardware topology class.
Since forcerec.h is still included by a few C files, the
previous cpuid datatype has been turned into pointers
to forward-declared non-existing structs, which causes
snew/sfree to choke on them. Internally they are instead
properly new:d/delete:d in the C++ code.

Change-Id: I378ec5dc6c32883c5d89f1cfeecea93a3b8b0e6b