RFR: 8353444: NMT: rename 'category' to 'MemTag' in malloc tracker

[Afshin Zafari]

Renamed usage of 'category' for 'MemTag' cases.

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Commit messages:
 - 8353444: NMT: rename 'category' to 'MemTag' in malloc tracker

Changes: https://git.openjdk.org/jdk/pull/25226/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25226&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8353444
  Stats: 63 lines in 8 files changed: 0 ins; 1 del; 62 mod
  Patch: https://git.openjdk.org/jdk/pull/25226.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25226/head:pull/25226

PR: https://git.openjdk.org/jdk/pull/25226