[skip ci] Document do_inheritance_check_on_method_ex() check_only and check params

These are quite confusingly named.

Zend/zend_inheritance.c

@@ -1065,6 +1065,11 @@ static void perform_delayable_implementation_check(
 	}
 }
 
+/**
+ * @param check_only Set to false to throw compile errors on incompatible methods, or true to return
+ *                   INHERITANCE_ERROR.
+ * @param checked Whether the compatibility check has already been performed by zend_can_early_bind().
+ */
 static zend_always_inline inheritance_status do_inheritance_check_on_method_ex(
 		zend_function *child, zend_class_entry *child_scope,
 		zend_function *parent, zend_class_entry *parent_scope,