[jdk21u] RFR: 8313368: (fc) FileChannel.size returns 0 on block special files

[Brian Burkhalter]

Backport of fix for JDK-8313368.

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Commit messages:
 - Backport 4ba81f631f572d870d0f2c96fefe0cabc55e1841

Changes: https://git.openjdk.org/jdk21u/pull/228/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=228&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8313368
  Stats: 11 lines in 2 files changed: 6 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk21u/pull/228.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/228/head:pull/228

PR: https://git.openjdk.org/jdk21u/pull/228