regen/embed.pl: Generate ARGS_ASSERT in more cases

This macro is actually always generated, but is empty if there are no
assertions needed.

Before this commit the code incorrectly generated an empty macro when
there were no arguments marked NN even when types were defined that
would call for asserts to be generated.

Author: khwilliamson

proto.h

@@ -362,9 +362,9 @@ sub generate_proto_h {
         $ret .= ";";
         $ret = "/* $ret */" if $has_mflag;
 
-        if ($args_assert_line || @names_of_nn) {
+        if ($args_assert_line || @names_of_nn || @typed_args) {
             $ret .= "\n#${ind}define PERL_ARGS_ASSERT_\U$plain_func\E";
-            if (@names_of_nn) {
+            if (@names_of_nn || @typed_args) {
                 $ret .= " \\\n";
 
                 my @asserts;