gn/cci.20210429: add apple arch option

[Alan5142]

Summary

Changes to recipe: gn/cci.20210429

Motivation

This PR fixes #25587. This bugfix allows the creation of binaries for other archs. The generator of gn is ignoring the arch passed when building the package.

Details

The changes involve adding arch flags to CFLAGS and LDFLAGS, allowing cross-compilation and universal binary support in macOS. They also include a change to allow passing the arch to other platforms, but the focus is on macOS.

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• Read the contributing guidelines
• Checked that this PR is not a duplicate: list of PRs by recipe
• Tested locally with at least one configuration using a recent version of Conan

[AbrilRBS]

Hi @Alan5142 thanks a lot for the PR

Sorry about the bot noises with the approval requirement, I'm approving these runs manually on our end until the approavl process completes, thanks for your understanding! :)

[conan-center-bot]

Conan v1 pipeline ✔️

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All green in build 4 (5fd09ca2cd1af0fee96de20279bf54a697f6b837):

• gn/cci.20240611:
  No packages built ⚠️ (All logs)

• gn/cci.20210429:
  Built 8 packages out of 11 (All logs)

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All green in build 4 (5fd09ca2cd1af0fee96de20279bf54a697f6b837):

• gn/cci.20240611:
  No packages built ⚠️ (All logs)

• gn/cci.20210429:
  Built 4 packages out of 5 (All logs)

[Alan5142]

Hi @AbrilRBS!
No problem, thanks for taking the time. :)

[Alan5142]

Hi @AbrilRBS,
Is there a way to check why some builds say INVALID_CONFIGURATION?
Thanks!