RFR: 8336021: Doccheck: valign not allowed for HTML5 in java.xml

[Joe Wang]

Remove valign Attribute from the javadoc for org.w3c.dom.Attr. The table looks good with the default setting.

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Commit messages:
 - 8336021: Doccheck: valign not allowed for HTML5 in java.xml

Changes: https://git.openjdk.org/jdk/pull/20117/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20117&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8336021
  Stats: 23 lines in 1 file changed: 0 ins; 2 del; 21 mod
  Patch: https://git.openjdk.org/jdk/pull/20117.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20117/head:pull/20117

PR: https://git.openjdk.org/jdk/pull/20117