[jdk17u-dev] RFR: 8309591: Socket.setOption(TCP_QUICKACK) uses wrong level

[Aleksey Shipilev]

Unclean backport to fix TCP_QUICKACK bug.

The backport is unclean, because AIX hunks could not be applied. The implementation of extended socket options on AIX went into JDK 21 with [JDK-8305089](https://bugs.openjdk.org/browse/JDK-8305089).

Additional testing:
 - [ ] Linux AArch64 fastdebug, `jdk_net`
 - [ ] Linux AArch64 fastdebug, `tier1 tier2 tier3`

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Commit messages:
 - Backport 56a73a6f0f3d38379cecea1de5eacb751febca95

Changes: https://git.openjdk.org/jdk17u-dev/pull/1664/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1664&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309591
  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1664.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1664/head:pull/1664

PR: https://git.openjdk.org/jdk17u-dev/pull/1664