[jdk21u] RFR: 8315549: CITime misreports code/total nmethod sizes

[Aleksey Shipilev]

Unclean backport to fix `-XX:+CITime` reporting. Does not apply cleanly, because the variable type has been changed in JDK 22.

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Commit messages:
 - Backport ab12c5d32fede04cbbf8c86b6461a0c71404cd69

Changes: https://git.openjdk.org/jdk21u/pull/133/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=133&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315549
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk21u/pull/133.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/133/head:pull/133

PR: https://git.openjdk.org/jdk21u/pull/133