Update with word change suggestion

ObsidianMinor · varkor · web-flow · commit 16547f5025dd · 2019-10-26T18:42:31.000-05:00
Co-Authored-By: varkor &lt;github@varkor.com&gt;
diff --git a/src/librustc_passes/error_codes.rs b/src/librustc_passes/error_codes.rs
@@ -554,7 +554,7 @@ trait Foo {
 
 E0666: r##"
 `impl Trait` types cannot appear nested in the
-generic types of other `impl Trait` types.
+generic arguments of other `impl Trait` types.
 
 Example of erroneous code:
 
