The object indicates the flow type of the instance TLP is
'forward(1)' or 'backward(2)' or 'bidirectional(3)' or
'forwardandbackward(4)'. Only 'forward(1)' and 'backward(2)'
can be configured when 'hwIpfpmDcpInstTlpRoleIndex' is
'mid-point(3)'. The value 'null(0)' represents that this
flow is not configured under the instance.