[jdk25u-dev] RFR: 8369881: C2: Unexpected node in SuperWord truncation: ReverseBytesS, ReverseBytesUS

[Vishal Chand]

Clean backport of [8369881](https://github.com/openjdk/jdk/commit/aa194c6a5a21aca64d454e4c5eeed1464c8f190b): C2: Unexpected node in SuperWord truncation: ReverseBytesS, ReverseBytesUS

Fixes fuzzer-discovered assert failure in SuperWord truncation for ReverseBytesS and ReverseBytesUS nodes. Adds missing nodes to truncation switch statement and includes test cases for both.

Additional Testing:
- [x] New regression test fails without the fix, passes with it.
- [x] Linux x86_64 server fastebug compiler tests.

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Commit messages:
 - Backport aa194c6a5a21aca64d454e4c5eeed1464c8f190b

Changes: https://git.openjdk.org/jdk25u-dev/pull/233/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u-dev&pr=233&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8369881
  Stats: 54 lines in 2 files changed: 53 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk25u-dev/pull/233.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u-dev.git pull/233/head:pull/233

PR: https://git.openjdk.org/jdk25u-dev/pull/233