RFR: 8296615: use of undeclared identifier 'IPV6_DONTFRAG'

[Xue-Lei Andrew Fan]

Hi,

May I have this update in jdk.net reviewed?

While build on MacOX, I run into the following issues:

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Commit messages:
 - 8296615: use of undeclared identifier 'IPV6_DONTFRAG'

Changes: https://git.openjdk.org/jdk/pull/11047/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11047&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8296615
  Stats: 4 lines in 1 file changed: 4 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/11047.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11047/head:pull/11047

PR: https://git.openjdk.org/jdk/pull/11047