libultrahdr: fix i686-linux build and unrestrict meta.platforms

[zwang20]

• fix i686-linux build
  • This pull request fixes the i686-linux build by adding -mfpmath=sse -msse2 to cflags, which fixes failing tests
  • This closes issue Build failure: i686-linux.libultrahdr #532626
• unrestrict meta.platforms
  • By applying the upstream pull request Remove platform and architecture detection logic google/libultrahdr#383, this allows for builds of arbitrary platforms.
• fix tests on big endian
  • This pull request fixes tests on big-endian by incorporating the upstream commit in fixes #382 google/libultrahdr#396, as requested by @OPNA2608

Things done

• Built on platform:
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
  • i686-linux
• Tested, as applicable:
  • NixOS tests in nixos/tests.
  • Package tests at passthru.tests.
  • Tests in lib/tests or pkgs/test for functions and "core" functionality.
• Ran nixpkgs-review on this PR. See nixpkgs-review usage.
• Tested basic functionality of all binary files, usually in ./result/bin/.
• Nixpkgs Release Notes
  • Package update: when the change is major or breaking.
• NixOS Release Notes
  • Module addition: when adding a new NixOS module.
  • Module update: when the change is significant.
• Fits CONTRIBUTING.md, pkgs/README.md, maintainers/README.md and other READMEs.
• Follows the automation/AI policy.

Review dismissed automatically

[yzx9]

The code LGTM, but I can’t test this since I don’t have access to a machine with that architecture, e.g. i686-linux.

cc @OPNA2608, who submitted the PR #527782 to restrict meta.platforms.

close: #532626

[OPNA2608]

Thanks for the ping. Please apply google/libultrahdr@13a058f to fix tests on big-endian.

[OPNA2608]

libultrahdr and imagemagick build with no issues on powerpc64-linux with this. Change seems fine to me.

Might want to fix the first commit: From: Your Name <you@example.com>

[OPNA2608]

LGTM, leaving final approval to @yzx9.