RFR: 8331410: Remove unused MemAllocator::mem_allocate_inside_tlab

[Albert Mingkun Yang]

Trivial removing dead code.

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Commit messages:
 - trivial

Changes: https://git.openjdk.org/jdk/pull/19019/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19019&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8331410
  Stats: 15 lines in 2 files changed: 0 ins; 15 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/19019.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19019/head:pull/19019

PR: https://git.openjdk.org/jdk/pull/19019