Add semicolon to OS case statement.

doc/classes/OS.xml

@@ -334,7 +334,7 @@
 				    case "Linux":
 				    case "FreeBSD":
 				    case "NetBSD":
-				    case "OpenBSD"
+				    case "OpenBSD":
 				    case "BSD":
 				        GD.Print("Linux/BSD");
 				        break;