[jfx11u] RFR: 8262396: Update Mesa 3-D Headers to version 21.0.3

[Kevin Rushforth]

Clean backport of Mesa-3D third-party update.

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Commit messages:
 - 8262396: Update Mesa 3-D Headers to version 21.0.3

Changes: https://git.openjdk.java.net/jfx11u/pull/27/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx11u&pr=27&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8262396
  Stats: 140 lines in 6 files changed: 100 ins; 18 del; 22 mod
  Patch: https://git.openjdk.java.net/jfx11u/pull/27.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx11u pull/27/head:pull/27

PR: https://git.openjdk.java.net/jfx11u/pull/27