[code-reflection] RFR: Opening Hat Dialect for Handling Barriers and Shared/Private Memory [v5]

[Juan Fumero]

> This patch creates a new dialect for HAT for handling barriers, local (or shared) memory declaration of types, and private memory declariton. It extends the `Op`s provided by code-reflection with a new `HatOp` the dialect.
> 
> It is enabled by default. 
> 
> TODO: We should move the Hat Config to a common place to be able to use it in the Hat core module, not just in the code gen.

Juan Fumero has updated the pull request incrementally with one additional commit since the last revision:

  [hat] dialects - refactor

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Changes:
  - all: https://git.openjdk.org/babylon/pull/560/files
  - new: https://git.openjdk.org/babylon/pull/560/files/215a6a01..60d1b148

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=560&range=04
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=560&range=03-04

  Stats: 83 lines in 5 files changed: 47 ins; 13 del; 23 mod
  Patch: https://git.openjdk.org/babylon/pull/560.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/560/head:pull/560

PR: https://git.openjdk.org/babylon/pull/560