ffmpeg: enable ffplay in small variant

[SuperSandro2000]

Description of changes

This is required for corrscope, also see #271863 (comment)

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 24.05 Release Notes (or backporting 23.05 and 23.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

---

Add a 👍 reaction to pull requests you find important.

[Atemu]

Result of nixpkgs-review pr 296128 run on x86_64-linux 1

7 packages built:

• ffmpeg
• ffmpeg.bin (ffmpeg.bin.bin ,ffmpeg.bin.data ,ffmpeg.bin.dev ,ffmpeg.bin.doc ,ffmpeg.bin.lib ,ffmpeg.bin.man)
• ffmpeg.data (ffmpeg.data.bin ,ffmpeg.data.data ,ffmpeg.data.dev ,ffmpeg.data.doc ,ffmpeg.data.lib ,ffmpeg.data.man)
• ffmpeg.dev (ffmpeg.dev.bin ,ffmpeg.dev.data ,ffmpeg.dev.dev ,ffmpeg.dev.doc ,ffmpeg.dev.lib ,ffmpeg.dev.man)
• ffmpeg.doc (ffmpeg.doc.bin ,ffmpeg.doc.data ,ffmpeg.doc.dev ,ffmpeg.doc.doc ,ffmpeg.doc.lib ,ffmpeg.doc.man)
• ffmpeg.lib (ffmpeg.lib.bin ,ffmpeg.lib.data ,ffmpeg.lib.dev ,ffmpeg.lib.doc ,ffmpeg.lib.lib ,ffmpeg.lib.man)
• ffmpeg.man (ffmpeg.man.bin ,ffmpeg.man.data ,ffmpeg.man.dev ,ffmpeg.man.doc ,ffmpeg.man.lib ,ffmpeg.man.man)