net/mlx4_core: Fixes for VF / Guest startup flow

- pass the following parameters:
  - firmware version (added QUERY_FW paravirtualization for that)

  - disable Blueflame on slaves. KVM disables write combining on guests,
    and we get better performance without BF in this case. (This requires
    QUERY_DEV_CAP paravirtualization, also in this commit)

  - max qp rdma as destination

- get rid of a chunk of "if (0)" dead code

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>