RFR: 8351241: Require minimum gcc version 12

[SendaoYan]

Hi all,

After [JDK-8345627](https://bugs.openjdk.org/browse/JDK-8345627), the minumum gcc version should be 12. [JDK-8345627](https://bugs.openjdk.org/browse/JDK-8345627) add gcc compile option -ftrivial-auto-var-init=pattern for debug build, -ftrivial-auto-var-init=pattern gcc option was supported since [gcc12](https://gcc.gnu.org/gcc-12/changes.html#uninitialized).

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Commit messages:
 - 8351241: Require minimum gcc version 12

Changes: https://git.openjdk.org/jdk/pull/23913/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23913&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8351241
  Stats: 3 lines in 3 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/23913.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23913/head:pull/23913

PR: https://git.openjdk.org/jdk/pull/23913