[jdk17u] RFR: 8267256: Extend minimal retry for loopback connections on Windows to PlainSocketImpl

[Mat Carter]

Building upon [JDK-8250521](https://bugs.openjdk.java.net/browse/JDK-8250521) which only added support for NIOSocketImpl (default), add support to PlainSocketImpl which can be selected as the implementation.

This is required for the backport to 11u where NIOSocketImpl doesn't exist and PlainSocketImpl is the default implementation

To test on windows run with -Djdk.net.usePlainSocketImpl

Before fix loopback timeouts:

- NioSocketImpl ~200ms
- PlainSocketImpl ~22200ms

After fix loopback timeouts:

- NioSocketImpl ~200ms
- PlainSocketImpl ~200ms

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Commit messages:
 - Removed whitespace
 - 8267256: minimal retry for loopback connections on Windows when PlainSocketImpl selected

Changes: https://git.openjdk.java.net/jdk17u/pull/153/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=153&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8267256
  Stats: 13 lines in 1 file changed: 13 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/153.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/153/head:pull/153

PR: https://git.openjdk.java.net/jdk17u/pull/153