Export to userspace the front panel name of the port, so that udev can
rename the ports accordingly. The convention suggested by switchdev
documentation is used:

1) Non-split: pX
2) Split: pXsY
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>