cxgb4vf: fix setting unicast/multicast addresses ...

We were truncating the number of unicast and multicast MAC addresses
supported.  Additionally, we were incorrectly computing the MAC Address
hash (a "1 << N" where we needed a "1ULL << N").

Signed-off-by: Casey Leedom <leedom@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>