RFR: 8369814: G1: Relax card mark and store ordering [v2]

[Albert Mingkun Yang]

> This PR removes the card-mark and store ordering constraint. The first commit changes `card_mark_must_follow_store` to `false` and the second commit removes all uses of `card_mark_must_follow_store`, because both the original method and its override are identical, and no GC have such ordering requirement any more.
> 
> Test: tier1-5

Albert Mingkun Yang has updated the pull request incrementally with one additional commit since the last revision:

  review

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Changes:
  - all: https://git.openjdk.org/jdk/pull/27794/files
  - new: https://git.openjdk.org/jdk/pull/27794/files/e424e898..1eed131b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27794&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27794&range=00-01

  Stats: 89 lines in 7 files changed: 0 ins; 85 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/27794.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27794/head:pull/27794

PR: https://git.openjdk.org/jdk/pull/27794