RFR: 8362611: [GCC static analyzer] memory leak in ps_core.c core_handle_note

[Lei Zhu]

Free the `buf` before the early return.

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Commit messages:
 - 8362611: [GCC static analyzer] memory leak in ps_core.c core_handle_note

Changes: https://git.openjdk.org/jdk/pull/26403/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26403&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8362611
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/26403.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26403/head:pull/26403

PR: https://git.openjdk.org/jdk/pull/26403