RFR: 8343789: Move mutable nmethod data out of CodeCache

[Boris Ulasevich]

This change relocates mutable data (such as relocations, oops, and metadata) from the nmethod. The change follows the recent PR #18984, which relocated immutable nmethod data from the CodeCache.

The core idea remains the same: use the CodeCache for executable code while moving additional data to the C heap. The primary motivations are improving security and enhancing code density.

Although performance is not the main focus, testing on AArch64 CPUs, where code density plays a significant role, has shown a 1–2% performance improvement in specific scenarios, such as the CodeCacheStress test and the Renaissance Dotty benchmark.

The numbers. Immutable data constitutes **~30%** on the nmehtod. Mutable data constitutes **~8%** of nmethod. Example (statistics collected on the CodeCacheStress benchmark):
- nmethod_count:134000, total_compilation_time: 510460ms
- total allocation time malloc_mutable/malloc_immutable/CodeCache_alloc: 62ms/114ms/6333ms,
- total allocation size (mutable/immutable/nmentod): 64MB/192MB/488MB

Functional testing: jtreg on arm/aarch/x86.
Performance testing: renaissance/dacapo/SPECjvm2008 benchmarks.

Alternative solution (see comments): In the future, relocations can be moved to _immutable_data.

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Commit messages:
 - remove _code_end_offset
 - update jvm.hotspot.code.CodeBlob class
 - update: mutable data for all CodeBlobs with relocations
 - fix stat printout
 - 8343789: Move mutable nmethod data out of CodeCache

Changes: https://git.openjdk.org/jdk/pull/21276/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21276&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8343789
  Stats: 193 lines in 8 files changed: 102 ins; 41 del; 50 mod
  Patch: https://git.openjdk.org/jdk/pull/21276.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21276/head:pull/21276

PR: https://git.openjdk.org/jdk/pull/21276