libavif: add pcre2 to fix cross

[ghost]

Description of changes

libavif appears to require pcre2, which it can find (indirectly) through the nativeBuildInputs for native builds. For cross builds we need to add it explicitly.

Error which this fixed:

-- Found PkgConfig: /nix/store/13a2qvyl3lfcw0i50kfzlry5apjagn9f-aarch64-unknown-linux-gnu-pkg-config-wrapper-0.29.2/bin/aarch64-unknown-linux-gnu-pkg-config (found version
"0.29.2")
-- Checking for one of the modules 'gdk-pixbuf-2.0'
Package libpcre2-8 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libpcre2-8.pc'
to the PKG_CONFIG_PATH environment variable
Package 'libpcre2-8', required by 'glib-2.0', not found
Package libpcre2-8 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libpcre2-8.pc'
to the PKG_CONFIG_PATH environment variable
Package 'libpcre2-8', required by 'glib-2.0', not found
Package libpcre2-8 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libpcre2-8.pc'
to the PKG_CONFIG_PATH environment variable
Package 'libpcre2-8', required by 'glib-2.0', not found
Package libpcre2-8 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libpcre2-8.pc'
to the PKG_CONFIG_PATH environment variable
Package 'libpcre2-8', required by 'glib-2.0', not found

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• 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/)
• 23.11 Release Notes (or backporting 23.05 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.

[lopsided98]

That error occurs in the native build as well, and appears to be caused by harmless missing Requires.private dependencies. The real error is later:

Builder called die: Cannot wrap '/nix/store/vnrgzs1llc6a9a7md9pnmgkzbcgqhy7z-gdk-pixbuf-armv6l-unknown-linux-gnueabihf-2.42.10/bin/gdk-pixbuf-thumbnailer' because it is not an executable file
Backtrace:
7 assertExecutable /nix/store/l27vvihygpnqcbjz34imfjj6dj2jx3bn-make-shell-wrapper-hook/nix-support/setup-hook
43 makeShellWrapper /nix/store/l27vvihygpnqcbjz34imfjj6dj2jx3bn-make-shell-wrapper-hook/nix-support/setup-hook
36 makeWrapper /nix/store/l27vvihygpnqcbjz34imfjj6dj2jx3bn-make-shell-wrapper-hook/nix-support/setup-hook
132 _callImplicitHook /nix/store/ypp192asf7wwb2da0df4v7c9jgd8mf7r-stdenv-linux/setup
144 _eval /nix/store/ypp192asf7wwb2da0df4v7c9jgd8mf7r-stdenv-linux/setup
87 runHook /nix/store/ypp192asf7wwb2da0df4v7c9jgd8mf7r-stdenv-linux/setup
1404 installPhase /nix/store/ypp192asf7wwb2da0df4v7c9jgd8mf7r-stdenv-linux/setup
1596 genericBuild /nix/store/ypp192asf7wwb2da0df4v7c9jgd8mf7r-stdenv-linux/setup
6 main /nix/store/6xg259477c90a229xwmb53pdfkn6ig3g-default-builder.sh

[lopsided98]

It looks like gdk-pixbuf simply doesn't support thumbnailers when cross-compiling: https://gitlab.gnome.org/GNOME/gdk-pixbuf/-/blob/master/meson.build#L376.

We should probably just disable gdk-pixbuf support in libavif when cross-compiling.

[ghost]

#250813