[StreamExecutor] Simplify Kernel classes

Summary:
Make the Kernel class follow the pattern of the other classes. It now
has a type-safe user wrapper and a typeless, platform-specific handle.

Reviewers: jlebar

Subscribers: jprice, parallel_libs-commits

Differential Revision: https://reviews.llvm.org/D24043

llvm-svn: 280176
GitOrigin-RevId: 90ce6e1e6496b222cf8e3022ed6f80ccc45dfc0e
7 files changed
tree: ef7bea5e0ac8e14c01d7f1a06fa174001a48fec0
  1. streamexecutor/
  2. .arcconfig
  3. .clang-format
  4. README.rst