Add a global variable cpuArch

[danny1113]

• Move arch string literal to a global variable cpuArch.
• Refactor: Let compiler to infer the array type.

[cmcgee1024]

Thanks @danny1113

This is a good clean up of some ugly code. I'm going to run the tests on this, but will need to wait a bit longer to merge it since we're trying to close off the 0.4.0 release leaving the branch open for last minute stability fixes.

[cmcgee1024]

@danny1113 can you reformat the new code following the instructions in the failed workflow here: https://github.com/swiftlang/swiftly/actions/runs/13129413293/job/36656660591?pr=216

[cmcgee1024]

@swift-ci test macOS

[cmcgee1024]

This all looks good to me and the checks are all passing. I'm not approving and merging it for now since there is a freeze on the main branch.

[danny1113]

This all looks good to me and the checks are all passing. I'm not approving and merging it for now since there is a freeze on the main branch.

Got it! Thanks!

[cmcgee1024]

Thanks @danny1113 for your contribution!