Upgrade libpng used for Splashscreen from 1.6.54 to 1.6.55 version. Testing is green with this update.
------------- Commit messages: - 8377526: Update Libpng to 1.6.55 Changes: https://git.openjdk.org/jdk/pull/29922/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29922&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8377526 Stats: 32 lines in 8 files changed: 7 ins; 0 del; 25 mod Patch: https://git.openjdk.org/jdk/pull/29922.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/29922/head:pull/29922 PR: https://git.openjdk.org/jdk/pull/29922
