[CMake] Match lowercase "aarch64"

[neonichu]

Seems like it is also possible for "aarch64" to be spelled lowercase, this fixes building on Ubuntu on arm at least.

[lorentey]

Gah, GitHub cannot do rebases. @neonichu can you please rebase this on top on release/1.0 instead of main?

[lorentey]

Looks good!

How are we supposed to test this case?

[neonichu]

Rebased on release/1.0.

In terms of testing, @shahmishal should be able to answer this. I am assuming we have some way of doing CI on aarch64, but not sure what it is.

[lorentey]

@swift-ci test

[shahmishal]

We should be able to cross pull request test this by creating a fake PR on Swift repo.

[lorentey]

We should be able to cross pull request test this by creating a fake PR on Swift repo.

IIUC, toolchain builds will only test tagged releases, by design. But that's still much better than nothing! 👍

[neonichu]

Looks like the toolchain build succeeded and I also tested locally in an aarch64 Docker container.

[tomerd]

@lorentey lmk when we have a tag and I will pull this in

[tomerd]

@lorentey lmk when we have a tag and I will pull this in

@lorentey any plans on tagging?

[lorentey]

@tomerd Oh, I'll make a new tag right now!

[lorentey]

1.0.1 is out now -- https://github.com/apple/swift-collections/releases/tag/1.0.1