fix lazylock comment

Signed-off-by: Xinye <xinye.tao@metabit-trading.com>

library/std/src/sync/lazy_lock.rs

@@ -226,7 +226,7 @@ pub fn force(this: &LazyLock<T, F>) -> &T {
 }
 
 impl<T, F> LazyLock<T, F> {
-    /// Returns a reference to the value if initialized, or `None` if not.
+    /// Returns a mutable reference to the value if initialized, or `None` if not.
     ///
     /// # Examples
     ///
@@ -255,7 +255,7 @@ pub fn get_mut(this: &mut LazyLock<T, F>) -> Option<&mut T> {
         }
     }
 
-    /// Returns a mutable reference to the value if initialized, or `None` if not.
+    /// Returns a reference to the value if initialized, or `None` if not.
     ///
     /// # Examples
     ///