[libx264/20220602] Add version

[MartinDelille]

---

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• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
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[uilianries]

I don't see that release on the snapshot page: https://download.videolan.org/pub/videolan/x264/snapshots/ Is is an official tag? Otherwise, I suggest you using the prefix cci.

[MartinDelille]

No: the snapshotting service is discontinued as you can read here:
https://download.videolan.org/pub/videolan/x264/snapshots/x264-snapshot-20191218-README.txt

For information, the 20191217 version isn't compatible with ffmpeg 5.1 (#12033)

I applied the prefix as suggested.

[conan-center-bot]

All green in build 2 (4217e35887d7759348f33aceae5a16262604341e):

• libx264/cci.20220602@:
  All packages built successfully! (All logs)

  🔸 Informative: This recipe is not ready for Conan v2

  _{We have started the migration process to Conan v2 and exporting recipes successfully will be required in the future.
  This is just an informative note to gain awareness about the process, no need to take any action. The plan is to enforce smaller steps that are easier to fix and, eventually, this conan export step will work.
  See the recipe migration guide to know more about the changes required.}

  ERROR: Error loading conanfile at '/home/conan/w/prod_cci_PR-12046/recipes/libx264/all/conanfile.py': Unable to load conanfile in /home/conan/w/prod_cci_PR-12046/recipes/libx264/all/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod_cci_PR-12046/recipes/libx264/all/conanfile.py", line 2, in <module>
      from conans import ConanFile, tools, AutoToolsBuildEnvironment
  ImportError: cannot import name 'ConanFile' from 'conans' (/opt/pyenv/versions/3.7.13/lib/python3.7/site-packages/conans/__init__.py)
  

[conan-center-bot]

This PR has been automatically merged due Bump version or Bump dependencies label.
Read https://github.com/conan-io/conan-center-index/blob/master/docs/labels.md#bump-version to obtain more information.