Remove needless returns detected by clippy in the compiler

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -1038,7 +1038,7 @@ fn report_trait_method_mismatch<'tcx>(
         false,
     );
 
-    return diag.emit();
+    diag.emit()
 }
 
 fn check_region_bounds_on_impl_item<'tcx>(

compiler/rustc_hir_analysis/src/coherence/builtin.rs

@@ -274,7 +274,7 @@ fn visit_implementation_of_dispatch_from_dyn(checker: &Checker<'_>) -> Result<()
                         return false;
                     }
 
-                    return true;
+                    true
                 })
                 .collect::<Vec<_>>();