Rollup merge of #111000 - JohnBobbo96:core_option_unneeded_function, r=jyn514

Remove unneeded function call in `core::option`.

r? `@jyn514`

library/core/src/option.rs

@@ -1007,7 +1007,7 @@ pub fn unwrap_or_default(self) -> T
     {
         match self {
             Some(x) => x,
-            None => Default::default(),
+            None => T::default(),
         }
     }
 
@@ -1615,11 +1615,7 @@ pub fn get_or_insert_default(&mut self) -> &mut T
     where
         T: Default,
     {
-        fn default<T: Default>() -> T {
-            T::default()
-        }
-
-        self.get_or_insert_with(default)
+        self.get_or_insert_with(T::default)
     }
 
     /// Inserts a value computed from `f` into the option if it is [`None`],