ra_hir_def: fix typo

crates/ra_hir_def/src/path.rs

@@ -95,7 +95,7 @@ pub struct Path {
     /// Note that paths like `<Type as Trait>::foo` are desugard to `Trait::<Self=Type>::foo`.
     type_anchor: Option<Box<TypeRef>>,
     mod_path: ModPath,
-    /// Invariant: the same len as self.path.segments
+    /// Invariant: the same len as `self.mod_path.segments`
     generic_args: Vec<Option<Arc<GenericArgs>>>,
 }