Auto merge of #32006 - jseyfried:fix_expanded_mod_path, r=nikomatsakis

This PR changes the search paths for macro-expanded non-inline modules so that they match ordinary non-inline modules (fixes #31624). This is a [breaking-change].

Right now, the search paths for a macro-expanded non-inline module are computed as if the module were declared in the top level of the file in which the macro was defined.
For example, consider `./foo/mod.rs`:
```rust
mod inconsequential { // moving the macro outside this module wouldn't change anything
    macro_rules! mod_decl {
        ($i:ident) => { mod $i; }
    }
}
```
and `./lib.rs`:
```rust
mod foo;

mod bar {
    mod_decl!(baz);
    //^ Now, rustc expects `./foo/baz.rs` (or `./foo/baz/mod.rs`)
    //| After this PR, rustc will expect `./bar/baz.rs` (or `./bar/baz/mod.rs`)
}
```
r? @alexcrichton

0 files changed, 0 insertions, 0 deletions