RFR: 8371779: Replace MemTagBitmap with ResourceBitMap

[Johan Sjölen]

Hi,

We don't really need our own bitmap implementation and can instead use the utility `ResourceBitMap`. This is a nice cleanup, imho.

Testing: GHA

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Commit messages:
 - Replace MemTagBitMap with BitMap

Changes: https://git.openjdk.org/jdk/pull/28285/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28285&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8371779
  Stats: 68 lines in 2 files changed: 4 ins; 59 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/28285.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28285/head:pull/28285

PR: https://git.openjdk.org/jdk/pull/28285