[jdk21u] RFR: 8315383: jlink SystemModulesPlugin incorrectly parses the options

[Mandy Chung]

Clean backports from the [openjdk/jdk](https://git.openjdk.org/jdk) repository:
-  commit [ea5aa61](https://github.com/openjdk/jdk/commit/ea5aa61c8cc5caa04f7c7eac9634df28011581dc)
-  commit [bc8e9f44](https://github.com/openjdk/jdk/commit/bc8e9f44a39ff59b59b2d1d5d546a148be75a2f2)

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Commit messages:
 - Backport ea5aa61c8cc5caa04f7c7eac9634df28011581dc
 - Backport bc8e9f44a39ff59b59b2d1d5d546a148be75a2f2

Changes: https://git.openjdk.org/jdk21u/pull/127/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=127&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315383
  Stats: 354 lines in 10 files changed: 347 ins; 2 del; 5 mod
  Patch: https://git.openjdk.org/jdk21u/pull/127.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/127/head:pull/127

PR: https://git.openjdk.org/jdk21u/pull/127