Returns current SuperServer connection type as one of:
AS400 - returned when you connect to an IBM i server with DEFINE_OS_400_SERVER (or DBID=*OS400)
RDMLX400 - returned when connect to an IBM i server with DEFINE_ANY_SERVER (or DBID=*ANY)
OTHER - returned when you connect to a Windows or Linux server
NONE - returned when you are not connected to a server.