rustc_mir_build: reorder bindings

No functional changes intended.

I'm playing around with building compiler components using nightly rust
(2021-11-02) in a non-standard way. I encountered the following error while
trying to build rustc_mir_build:

```
error[E0597]: `wildcard` does not live long enough
    --> rust/src/nightly/compiler/rustc_mir_build/src/build/matches/mod.rs:1767:82
     |
1767 |         let mut otherwise_candidate = Candidate::new(expr_place_builder.clone(), &wildcard, false);
     |                                                                                  ^^^^^^^^^ borrowed value does not live long enough
...
1799 |     }
     |     -
     |     |
     |     `wildcard` dropped here while still borrowed
     |     borrow might be used here, when `guard_candidate` is dropped and runs the destructor for type `Candidate<'_, '_>`
     |
     = note: values in a scope are dropped in the opposite order they are defined
```

I believe this flags an issue that may become an error in the future.
Swapping the order of `wildcard` and `guard_candidate` resolves it.

0 files changed, 0 insertions, 0 deletions