Remove param from diagnostics in the empty case

Author: adpaco-aws

src/goto-programs/goto_convert_functions.cpp

@@ -170,9 +170,7 @@ void goto_convert_functionst::convert_function(
       !p.empty(),
       "parameter identifier should not be empty",
       "function:",
-      identifier,
-      "parameter:",
-      p);
+      identifier);
 
     DATA_INVARIANT_WITH_DIAGNOSTICS(
       symbol_table.has_symbol(p),