[lworld] RFR: 8304084: [lworld] Fix copyright text in GensrcValueClasses.gmk

[Roger Riggs]

Correct incomplete copyright.

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Commit messages:
 - 8304084: [lworld] Fix copyright text in GensrcValueClasses.gmk

Changes: https://git.openjdk.org/valhalla/pull/830/files
 Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=830&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8304084
  Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/valhalla/pull/830.diff
  Fetch: git fetch https://git.openjdk.org/valhalla pull/830/head:pull/830

PR: https://git.openjdk.org/valhalla/pull/830