RFR: 8355668: RISC-V: jdk/incubator/vector/Int256VectorTests.java fails when using RVV

[Gui Cao]

Hi, After https://github.com/openjdk/jdk/pull/24129, some tests run failed. due to the fact that the later predicate condition overrides the previous one.

### Testing
qemu-system 9.1.50 with UseRVV:

- [x] Run test/jdk/jdk/incubator/vector (fastdebug)

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Commit messages:
 - 8355668: RISC-V: jdk/incubator/vector/Int256VectorTests.java fails when using RVV

Changes: https://git.openjdk.org/jdk/pull/24910/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24910&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8355668
  Stats: 20 lines in 1 file changed: 0 ins; 8 del; 12 mod
  Patch: https://git.openjdk.org/jdk/pull/24910.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24910/head:pull/24910

PR: https://git.openjdk.org/jdk/pull/24910