These are identified by misc-include-cleaner. I've filtered out those
that break builds. Also, I'm staying away from llvm-config.h,
config.h, and Compiler.h, which likely cause platform- or
compiler-specific build failures.
This patch implements a rewrite pattern for transforming gpu.global_id x
to gpu.thread_id + gpu.block_id * gpu.block_dim.
Reviewed By: makslevental
Differential Revision: https://reviews.llvm.org/D148978
