RFR: 8261845: File permissions of packages built by jpackage

[Alexander Matveev]

- Fixed by adding write permissions to .exe package.

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Commit messages:
 - 8261845: File permissions of packages built by jpackage

Changes: https://git.openjdk.java.net/jdk/pull/2822/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2822&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8261845
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2822.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2822/head:pull/2822

PR: https://git.openjdk.java.net/jdk/pull/2822