Change ofp_if_type() to use ifnet->if_type.
Change ofp_if_type() to use ifnet->if_type.

Signed-off-by: Janne Peltonen <184f24496cb678cb2ae7fb0b4232a4cbe2bea47a@nokia.com>
Reviewed-by: Jere Leppänen <14957520de8d9815e0c353a07fe23c737f0171e9@nokia.com>
Reviewed-by: Valentin Radulescu <5c0267d222138450b4835b40b746ecdf0117cfc8@enea.com>

OpenFastPath/ofp,OpenFastPath/ofp,OpenFastPath/ofp,OpenFastPath/ofp