Looks like sockets.pp is not in the uses clause. The fp* units from fcl-net will pull those consts and enumerations in from sockets. Add sockets to the uses clause.
Then the previous statement would also have failed.
Check if the declaration of the SockAddr variable has changed and /or is correct instead. SockAddr is type TInetSockAddr. Some of the FP code declare it as Addr only, like in ssockets.pp. (double s is correct here)