Fix Redox CI

[josephlr]

Fixes #79

[newpavlov]

Hopefully rust-lang/rust#63521 will land soon and we will not have to use xbuild for Redox.

[newpavlov]

@josephlr
Can you revert to the old cargo build? The builder PR has landed, so we should get pre-built Redox std soon.

[josephlr]

@newpavlov will do. Looks like redox is now back to building in the latest nightly.
https://rust-lang.github.io/rustup-components-history/x86_64-unknown-redox.html

[newpavlov]

Argh, looks like libc is still broken on Redox...

[josephlr]

Argh, looks like libc is still broken on Redox...

I confirmed locally that 0.2.62 seems to fix things. So this can be merged once the CI passes.

[josephlr]

Whoops @newpavlov, I thought you had approved this, so I merged it. We should probably enable the feature that requires review before merging. Would that work for you?

[newpavlov]

Yeah, no problem. I am not sure if we need this setting, but either way, I think we will need @dhardy for that.

[dhardy]

Done