[jdk21u] RFR: 8322790: RISC-V: Tune costs for shuffles with no conversion

[Ilya Gavrilin]

Hi all, I would like to backport [JDK-8322790](https://bugs.openjdk.org/browse/JDK-8322790) to jdk21u in order to improve performance for methods operating with integer representations of floating point values.
Patch applies clean, backported to jdk22u.

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Commit messages:
 - Backport 2acb5bd9924511b58b0e57ea9eb6c2dee9fd3ee8

Changes: https://git.openjdk.org/jdk21u/pull/434/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=434&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8322790
  Stats: 5 lines in 1 file changed: 1 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk21u/pull/434.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/434/head:pull/434

PR: https://git.openjdk.org/jdk21u/pull/434