Rollup merge of #93463 - dtolnay:_args, r=cjgillot

Rename _args -> args in format_args expansion

As observed in https://github.com/rust-lang/rust/pull/91359#discussion_r786058960, prior to that PR this variable was sometimes never used, such as in the case of:

```rust
println!("");

// used to expand to:
::std::io::_print(
    ::core::fmt::Arguments::new_v1(
        &["\n"],
        &match () {
            _args => [],
        },
    ),
);
```

so the leading underscore in `_args` was used to suppress an unused variable lint. However after #91359 the variable is always used when present, as the unused case would instead expand to:

```rust
::std::io::_print(::core::fmt::Arguments::new_v1(&["\n"], &[]));
```

0 files changed, 0 insertions, 0 deletions