RFR: 8325068: runtime/os/TestTracePageSizes.java: incorrect page size comparison for kernels < 5.0 with THP 'always' mode

[Sonia Zaldana Calles]

Hi all, 

This PR addresses [8325068](https://bugs.openjdk.org/browse/JDK-8325068) by disabling the test if running a kernel version < 5.0 with THP 'always' mode enabled. 

On older kernels, when THP mode is "always," the test fails because it doesn’t find the `THPeligible` field to identify that a mapping uses THP. As a result, it incorrectly compares the logged page size to the smaller page size reported in `/proc/self/smaps`.

Thanks, 
Sonia

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Commit messages:
 - 8325068: runtime/os/TestTracePageSizes.java: incorrect page size comparison for kernels < 5.0 with THP 'always' mode

Changes: https://git.openjdk.org/jdk/pull/23304/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23304&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8325068
  Stats: 9 lines in 1 file changed: 8 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/23304.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23304/head:pull/23304

PR: https://git.openjdk.org/jdk/pull/23304