RFR: 8316969: Improve CDS module graph support for --module option [v8]

[Calvin Cheung]

> Please review this changeset for adding support for `--module` (-m) option for CDS.
> Changes in the `ModuleBootstrap.java` are needed so that the `ArchivedModuleGraph.archive` and `ArchivedBootLayer.archive` are called if the main module is specified. The module name will be stored in the ro region of the CDS archive. During runtime, the archived module name will be compared with the runtime module name. If comparison fails, the archived full module graph won't be used.
> 
> Note: this RFE is a subtask of [JDK-8266329](https://bugs.openjdk.org/browse/JDK-8266329). More subtask(s) will be created to support other options such as `--add-modules`.
> 
> Passed tiers 1 - 4 testing.

Calvin Cheung has updated the pull request incrementally with one additional commit since the last revision:

  more comments from Alan and Ioi; copyright year update

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Changes:
  - all: https://git.openjdk.org/jdk/pull/16016/files
  - new: https://git.openjdk.org/jdk/pull/16016/files/daec9915..b214fa7c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16016&range=07
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16016&range=06-07

  Stats: 27 lines in 3 files changed: 23 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/16016.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16016/head:pull/16016

PR: https://git.openjdk.org/jdk/pull/16016