Rollup merge of #51629 - topecongiro:multiple-semicolon-in-local-span, r=petrochenkov

Do not consume semicolon twice while parsing local statement

The span for a `let` statement includes multiple semicolons. For example,

```rust
    let x = 2;;;
//  ^^^^^^^^^^^ The span for the above statement.
```

This PR fixes it.

cc https://github.com/rust-lang-nursery/rustfmt/issues/2791.

diff --cc src/libsyntax/parse/parser.rs
Simple merge