Binds pcb to the local address indicated by
ipaddr and port indicated by
port. ipaddr can be
IP_ADDR_ANY to indicate that it should listen
to any local IP address. Port may be 0 for
any port.
Return value
This function can return ERR_USE if all usable UDP
dynamic ports are used (only relevant if port
is 0. Otherwise udp_bind()
will always return ERR_OK.
