RFR: 8370578: SystemMapTest.java#normal fails intermittendly on macOS aarch64 [v2]

[Simon Tooke]

> This PR addresses [JDK-8370578](https://bugs.openjdk.org/browse/JDK-8370578)  
> 
> Under certain circumstances, OpenJDK on macOS maps the hsperf segment private instead of shared; one of those cases is hit during the tier1 tests, which test for that.  
> 
> This PR allows for shared or private mapping; the purpose of the intermittently failing test is to test System.map implementation, not JDK internals.

Simon Tooke has updated the pull request incrementally with one additional commit since the last revision:

  reformat comment block

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Changes:
  - all: https://git.openjdk.org/jdk/pull/28025/files
  - new: https://git.openjdk.org/jdk/pull/28025/files/8a33c39c..b2f8224e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28025&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28025&range=00-01

  Stats: 4 lines in 1 file changed: 2 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/28025.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28025/head:pull/28025

PR: https://git.openjdk.org/jdk/pull/28025