[code-reflection] Integrated: ffi apply clang tidy hints to ffi cuda/opencl common code

[Gary Frost]

A lot of ffi-code changes here.  

Mostly applying fixes recommended by clang tidy. 

Also spotted more opportunity for merging common opencl/ptx/cuda code.

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Commit messages:
 - ws
 - Merge code-reflection
 - ffi apply clang tidy hints to ffi cuda/opencl common code

Changes: https://git.openjdk.org/babylon/pull/451/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=451&range=00
  Stats: 3864 lines in 62 files changed: 1083 ins; 1269 del; 1512 mod
  Patch: https://git.openjdk.org/babylon/pull/451.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/451/head:pull/451

PR: https://git.openjdk.org/babylon/pull/451