[jfx17u] RFR: 8283218: Update GStreamer to 1.20.1

Mon May 9 21:14:14 UTC 2022

Almost clean backport to `jfx17u`. Tested in connection with libffi update in the `test-kcr-17.0.4` branch.

The only difference from the mainline patch is that the following file is not present in `jfx17u`, so that part of the patch was skipped:

modules/javafx.media/src/main/native/gstreamer/gstreamer-lite/gst-plugins-good/gst/audioparsers/gstaacparse.c

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Commit messages:
 - 8283218: Update GStreamer to 1.20.1

Changes: https://git.openjdk.java.net/jfx17u/pull/54/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx17u&pr=54&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8283218
  Stats: 38921 lines in 412 files changed: 22007 ins; 5981 del; 10933 mod
  Patch: https://git.openjdk.java.net/jfx17u/pull/54.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx17u pull/54/head:pull/54

PR: https://git.openjdk.java.net/jfx17u/pull/54