In JDK 16 we deprecated the old signal and sigset signal-chaining interfaces under [JDK-8257572](https://bugs.openjdk.org/browse/JDK-8257572). The deprecation warning was written to stdout but all other warnings go to stderr. Having the warning be on stdout causes interference with application output so we change it to stderr.
Testing - examined signal test output (see JBS issue) - tiers 1-3 sanity Thanks ------------- Commit messages: - 8344646: The libjsig deprecation warning should go to stderr not stdout Changes: https://git.openjdk.org/jdk/pull/22283/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22283&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8344646 Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod Patch: https://git.openjdk.org/jdk/pull/22283.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/22283/head:pull/22283 PR: https://git.openjdk.org/jdk/pull/22283
