RFR: 8263236: runtime/os/TestTracePageSizes.java fails on old kernels

[Aleksey Shipilev]

See the bug report for details. On some kernels, the madvise hint is not reflected in `/proc/smaps`. Instead, we can use a secondary evidence and read `AnonHugePages`.

Additional testing:
 - [x] Test with kernel 5.4.0 (still passes)
 - [x] Test with kernel 4.9.0 (used to fail, now passes)

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Commit messages:
 - Make jcheck happy: remove the TAB
 - 8263236: runtime/os/TestTracePageSizes.java fails on old kernels

Changes: https://git.openjdk.java.net/jdk/pull/3415/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3415&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263236
  Stats: 62 lines in 1 file changed: 40 ins; 1 del; 21 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3415.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3415/head:pull/3415

PR: https://git.openjdk.java.net/jdk/pull/3415