Exhaustive match on CoroutineKind

Author: metamuffin

compiler/rustc_trait_selection/src/error_reporting/infer/suggest.rs

@@ -172,7 +172,11 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                 hir::CoroutineDesugaring::Async | hir::CoroutineDesugaring::AsyncGen,
                 _,
             )) => (),
-            _ => return,
+            None
+            | Some(
+                hir::CoroutineKind::Coroutine(_)
+                | hir::CoroutineKind::Desugared(hir::CoroutineDesugaring::Gen, _),
+            ) => return,
         }
 
         if let ObligationCauseCode::CompareImplItem { .. } = cause.code() {