[OpenMP][AMDGPU] More detail in AMDGPU kernel launch info

Makes the info that is printed for kernel launches configurable for
different plugins. Adds all machinery to print the detailed launch
info that the current AMD plugin provides and includes e.g. register
spill counts.

The files msgpack.cpp, msgpack.def, and msgpack.h are copied from the old plugin
and are untouched. The contents of UtilitiesHSA.cpp and .h are copied together from
various files from the old plugin. The code was originally written by
Jon Chesterfield. I updated the function and type names visible to the outside, i.e.
in headers, to respect the LLVM conventions.

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D144521