Add links to the reference and rust by example for asm! docs and lints

These were previously removed in rust-lang#91728 due to broken links.

cc `@ehuss` since this updates the rust-by-example submodule

This is a necessary prerequisite of rust-lang#92611, to make a new page exist and satisfy the link checker.

…askrgr

Rollup of 10 pull requests

Successful merges:

 - rust-lang#92611 (Add links to the reference and rust by example for asm! docs and lints)
 - rust-lang#93158 (wasi: implement `sock_accept` and enable networking)
 - rust-lang#93239 (Add os::unix::net::SocketAddr::from_path)
 - rust-lang#93261 (Some unwinding related cg_ssa cleanups)
 - rust-lang#93295 (Avoid double panics when using `TempDir` in tests)
 - rust-lang#93353 (Unimpl {Add,Sub,Mul,Div,Rem,BitXor,BitOr,BitAnd}<$t> for Saturating<$t>)
 - rust-lang#93356 (Edit docs introduction for `std::cmp::PartialOrd`)
 - rust-lang#93375 (fix typo `documenation`)
 - rust-lang#93399 (rustbuild: Fix compiletest warning when building outside of root.)
 - rust-lang#93404 (Fix a typo from rust-lang#92899)

Failed merges:

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

Add links to the reference and rust by example for asm! docs and lints

These were previously removed in rust-lang#91728 due to broken links.

cc ``@ehuss`` since this updates the rust-by-example submodule

[beta] Backports

Backports of:

* rust-lang#92611 — Add links to the reference and rust by example for asm! docs and lints
* rust-lang#92983 — Update Linux runners to Ubuntu 20.04
* rust-lang#93081 — Update LLVM submodule
* rust-lang#93394 — Don't allow {} to refer to implicit captures in format_args.
* Cargo:
    * rust-lang/cargo#10377 — Remove strip = "off" (and undocumented strip = "n"/strip = "no")