[code-reflection] Integrated: Fix cuda cmake errors

[Gary Frost]

Testing maven and cmake changes on CUDA platform yielded some errors. 

Here we fix the top level CMakeLists.txt and the backends/cuda/CMakeLists.txt

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Commit messages:
 - Fix cuda cmake errors

Changes: https://git.openjdk.org/babylon/pull/116/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=116&range=00
  Stats: 17 lines in 2 files changed: 9 ins; 1 del; 7 mod
  Patch: https://git.openjdk.org/babylon/pull/116.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/116/head:pull/116

PR: https://git.openjdk.org/babylon/pull/116