bnx2x: prevent FW assert on low mem during unload

Buffers for FW statistics were allocated at an inappropriate time; In a machine
where the driver encounters problems allocating all of its queues, the driver
would still create FW requests for the statistics of the non-existing queues.
The wrong order of memory allocation could lead to zeroed statistics messages
being sent, leading to fw assert in case function 0 was down.

This changes the order of allocations, guaranteeing that statistic requests will
only be generated for actual queues.

Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>