[code-reflection] Integrated: Fixed up ptx backend (native) so that PTX work can begin

[Gary Frost]

Synced ptx native code to changes made for OpenCL+CUDA. 

This allows PTX java backend work to commence.

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Commit messages:
 - Fixed up ptx backend (native) so that PTX work can begin

Changes: https://git.openjdk.org/babylon/pull/104/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=104&range=00
  Stats: 38 lines in 6 files changed: 27 ins; 1 del; 10 mod
  Patch: https://git.openjdk.org/babylon/pull/104.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/104/head:pull/104

PR: https://git.openjdk.org/babylon/pull/104