RFR: 8356020: Failed assert in virtualMemoryTracker.cpp

[Calvin Cheung]

This is a temporary fix. The real fix needs more investigation in the NMT area. The change is just to pass `mtNone` as the `mem_tag` when calling `MemoryReserver::reserve()`.

Testing:

- Ran the test group `open/test/hotspot/jtreg:hotspot_aot_classlinking` 40 times on linux-aarch64 with the options: `-XX:+AOTClassLinking -XX:MaxRAMPercentage=6.25`
- tier1
- tiers 2 - 3 (in progress)

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Commit messages:
 - 8356020: Failed assert in virtualMemoryTracker.cpp

Changes: https://git.openjdk.org/jdk/pull/25054/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25054&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8356020
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/25054.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25054/head:pull/25054

PR: https://git.openjdk.org/jdk/pull/25054