rcll: tune down error about invalid workpiece ID to an info message

Currently, all our workpieces have invalid IDs, as the assumptions about
the IDs are wrong. For now, just tune down the error message to a
regular info message.

src/games/rcll/workpieces.clp

@@ -18,7 +18,7 @@
 		then (return BASE_SILVER))
 	(if (and (>= ?id (nth$ 1 ?*WORKPIECE-RANGE-CLEAR*)) (<= ?id (nth$ 2 ?*WORKPIECE-RANGE-CLEAR*)))
 			then (return BASE_CLEAR))
-	(printout error "Invalid workpiece ID " ?id ". Cannot determine base color." crlf)
+	(printout t "Invalid workpiece ID " ?id ". Cannot determine base color." crlf)
 	(return BASE_INVALID)
 )