[jdk21u-dev] RFR: 8340313: Crash due to invalid oop in nmethod after C1 patching

[Goetz Lindenmaier]

I backport this for parity with 21.0.7-oracle.

I had to do trivial resolves:

src/hotspot/cpu/riscv/nativeInst_riscv.cpp
The first lock to be changed already uses CodeCache_lock.

src/hotspot/share/runtime/mutexLocker.cpp/hpp
Resolved due to context

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Commit messages:
 - Backport 58d39c317e332fda994f66529fcd1a0ea0e53151

Changes: https://git.openjdk.org/jdk21u-dev/pull/1284/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1284&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8340313
  Stats: 166 lines in 10 files changed: 145 ins; 7 del; 14 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1284.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1284/head:pull/1284

PR: https://git.openjdk.org/jdk21u-dev/pull/1284