[code-reflection] Integrated: Hat more codegen cleanup

[Gary Frost]

Discovered more opportunities for c99 codegen cleanup. 

Lots of dead code removed as well as refactoring of common CodeBuilder patterns. 

PTXCodeBuilder can now be refactored to use the CodeBuilderContext and BabylonOpBuilder iface to simplify code gen

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Commit messages:
 - removed StreamCounter
 - removing dead code, simplified StremCounted code
 - moved common code to OpTk

Changes: https://git.openjdk.org/babylon/pull/553/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=553&range=00
  Stats: 1331 lines in 17 files changed: 522 ins; 641 del; 168 mod
  Patch: https://git.openjdk.org/babylon/pull/553.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/553/head:pull/553

PR: https://git.openjdk.org/babylon/pull/553