[jdk22u] RFR: 8330094: RISC-V: Save and restore FRM in the call stub

[Gui Cao]

Hi, The same issue also exists in jdk22u. So I would like to backport 8330094 to jdk22u. With this change, we save and restore the default floating-point control state when we enter and leave Java code, ensuring that we are still Java compatible if we're called via the JNI invocation interface with a weird FP control state. RISC-V specific change, risk is low.
The backport is not clean because jdk22u has no [JDK-8321021](https://bugs.openjdk.org/browse/JDK-8321021)

### Testing

- [x]  Run tier1 tests on SOPHON SG2042 (release)

-------------

Commit messages:
 - Backport 8330094: RISC-V: Save and restore FRM in the call stub

Changes: https://git.openjdk.org/jdk22u/pull/174/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk22u&pr=174&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8330094
  Stats: 34 lines in 3 files changed: 21 ins; 9 del; 4 mod
  Patch: https://git.openjdk.org/jdk22u/pull/174.diff
  Fetch: git fetch https://git.openjdk.org/jdk22u.git pull/174/head:pull/174

PR: https://git.openjdk.org/jdk22u/pull/174