cl-structures::Interned: Change to_ref() from assoc. function to member function

(it's so much nicer)

compiler/cl-structures/src/intern.rs

@@ -37,8 +37,8 @@ pub mod interned {
         }
 
         /// Gets the internal value as a reference with the interner's lifetime
-        pub fn to_ref(interned: &Self) -> &'a T {
-            interned.value
+        pub fn to_ref(&self) -> &'a T {
+            self.value
         }
     }