net/bnxt: support meta flow items to match on traffic source

net/bnxt: support meta flow items to match on traffic source

Add support for items PORT_REPRESENTOR and REPRESENTED_PORT
based on the existing support for item PORT_ID.

The use of item PORT_ID depends on the specified direction attribute.
Items PORT_REPRESENTOR and REPRESENTED_PORT, in turn, define traffic
direction themselves. The former matches traffic from the driver's
vNIC. The latter matches packets from either a v-port (network) or
a VF's vNIC (if the driver's port is a VF representor).

Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>