Tidy up redundant returns.

cont.c

@@ -2477,9 +2477,7 @@ fiber_resume_kw(rb_fiber_t *fiber, int argc, const VALUE *argv, int kw_splat)
         rb_raise(rb_eFiberError, "attempt to resume a transferring fiber");
     }
 
-    VALUE result = fiber_switch(fiber, argc, argv, kw_splat, fiber, false);
-
-    return result;
+    return fiber_switch(fiber, argc, argv, kw_splat, fiber, false);
 }
 
 VALUE

variable.c

@@ -2722,9 +2722,7 @@ rb_autoload_load(VALUE module, ID name)
     arguments.flag = ce->flag & (CONST_DEPRECATED | CONST_VISIBILITY_MASK);
 
     // Only one thread will enter here at a time:
-    VALUE result = rb_mutex_synchronize(arguments.mutex, autoload_try_load, (VALUE)&arguments);
-
-    return result;
+    return rb_mutex_synchronize(arguments.mutex, autoload_try_load, (VALUE)&arguments);
 }
 
 VALUE