RFR: 8269029: compiler/codegen/TestCharVect2.java fails for client VMs

[Christoph Göttschkes]

This reverts parts of the changes done by 7320e051eade3f22d28f11aef9c5effe324f0b79.

The introduced `CompileCommand` is still present, but the test case is again split up into two parts, one generic (without the `MaxVectorSize` flag), and one C2 specific with that flag. This fixes the test case for C1.

We could also keep the current test structure and add `IgnoreUnrecognizedVMOptions` for the later three `run`s, but this would execute the same test case multiple times if a client VM is tested.

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Commit messages:
 - Split up test, generic and C2 specific.

Changes: https://git.openjdk.java.net/jdk/pull/4530/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4530&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8269029
  Stats: 8 lines in 1 file changed: 8 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4530.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4530/head:pull/4530

PR: https://git.openjdk.java.net/jdk/pull/4530