gnomish wizard follow-up

Limit the race restriction to gnomes  to avoid
unanticipated problems with other species.

src/polyself.c

@@ -306,7 +306,8 @@ boolean forcecontrol;
 	/* The below polyok() fails either if everything is genocided, or if
 	 * we deliberately chose something illegal to force newman().
 	 */
-	if (!polyok(&mons[mntmp]) || !rn2(5) || your_race(&mons[mntmp]))
+	if (!polyok(&mons[mntmp]) || !rn2(5)
+		|| (Race_if(PM_GNOME) && your_race(&mons[mntmp])))
 		newman();
 	else if(!polymon(mntmp)) return;