change the order of type arguments on ControlFlow

This allows ControlFlow<BreakType> which is much more ergonomic for
common iterator combinator use cases.

compiler/rustc_data_structures/src/graph/iterate/mod.rs

@@ -87,8 +87,7 @@ where
 }
 
 /// Allows searches to terminate early with a value.
-// FIXME (#75744): remove the alias once the generics are in a better order and `C=()`.
-pub type ControlFlow<T> = std::ops::ControlFlow<(), T>;
+pub use std::ops::ControlFlow;
 
 /// The status of a node in the depth-first search.
 ///