Perform CQ initialization in the driver when the capability is supported
by the FW.  When passing the CQ to HW indicate that the CQ buffer has
been pre-initialized.

Doing so decreases CQ creation time.  Testing on P8 showed a single 2048
entry CQ creation time was reduced from ~395us to ~170us, which is
2.3x faster.
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>