[jdk11u-dev] RFR: 8255035: Update BCEL to Version 6.5.0

[Goetz Lindenmaier]

I backport this for parity with 11.0.15-oracle.

I had to resolve the copyright in two files.

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Commit messages:
 - Backport 1a0ff28ea10aaba53c5fbeb59800d3bcb1d228bc

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/687/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=687&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8255035
  Stats: 2149 lines in 95 files changed: 98 ins; 33 del; 2018 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/687.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/687/head:pull/687

PR: https://git.openjdk.java.net/jdk11u-dev/pull/687