Rollup merge of #84940 - jyn514:ninja, r=Mark-Simulacrum
Rollup merge of #84940 - jyn514:ninja, r=Mark-Simulacrum

Don't run sanity checks for `x.py setup`

These requirements change as soon as the command finishes running, and
`setup` doesn't build anything, so the check doesn't make sense.

Previously, `x.py setup` would give hard errors if `ninja` and `cmake`
were not installed, even if the new profile didn't require them.

Fixes https://github.com/rust-lang/rust/issues/84938.

aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust