Auto merge of #122113 - matthiaskrgr:rollup-5d1jnwi, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #121958 (Fix redundant import errors for preload extern crate)
 - #121976 (Add an option to have an external download/bootstrap cache)
 - #122022 (loongarch: add frecipe and relax target feature)
 - #122026 (Do not try to format removed files)
 - #122027 (Uplift some feeding out of `associated_type_for_impl_trait_in_impl` and into queries)
 - #122063 (Make the lowering of `thir::ExprKind::If` easier to follow)
 - #122074 (Add missing PartialOrd trait implementation doc for array)
 - #122082 (remove outdated fixme comment)
 - #122091 (Note why we're using a new thread in `test_get_os_named_thread`)

r? `@ghost`
`@rustbot` modify labels: rollup