RFR: 8339710: Avoid initializing AccessFlag related classes in write-only cases [v2]

[Claes Redestad]

> This PR reduces number of classes loaded on a minimal lambda bootstrapping test by 4 by avoiding the need to pull in some AccessFlag classes.

Claes Redestad has updated the pull request incrementally with one additional commit since the last revision:

  Add DMB.withFlags for consistency

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Changes:
  - all: https://git.openjdk.org/jdk/pull/20904/files
  - new: https://git.openjdk.org/jdk/pull/20904/files/fc90e83d..df6e8e89

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20904&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20904&range=00-01

  Stats: 6 lines in 1 file changed: 6 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/20904.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20904/head:pull/20904

PR: https://git.openjdk.org/jdk/pull/20904