[OpenMP] Support for OpenMP-Offload Record Replay

Enable record-replay for OpenMP offload kernels.  On recording the initialization
is performed on device initialization by reading env variables. (This is similar to
the way rr used to operate). The primary change takes place in the replay phase
with the replay tool explicitly initializing the record-replay functionality.

Differential Revision: https://reviews.llvm.org/D156174

Fix