[code-reflection] Integrated: Fix regression in last PR

[Gary Frost]

Turns out a VarOp instanceof check does not work here. For NVidia

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Commit messages:
 - Fix regression in last PR

Changes: https://git.openjdk.org/babylon/pull/756/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=756&range=00
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/babylon/pull/756.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/756/head:pull/756

PR: https://git.openjdk.org/babylon/pull/756