sfc: display vadaptor statistics for all interfaces

All interfaces will display vadaptor statistics, so set all the
relevant bits in the stats bitmask. Only functions with the
LINKCTRL flag will see other stats, including (per-port) MAC stats.

The vadaptor stats are from rx_unicast to tx_overflow.

Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>