RFR: 8289095: (fs) UnixCopyFile build error on linux-x86

[Brian Burkhalter]

Use `(char*)jlong_to_ptr(address)` instead of the straight cast `(char*)address`.

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Commit messages:
 - 8289095: (fs) UnixCopyFile build error on linux-x86

Changes: https://git.openjdk.org/jdk/pull/9265/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9265&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8289095
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/9265.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9265/head:pull/9265

PR: https://git.openjdk.org/jdk/pull/9265