[BNX2X]: fix slowpath races and locking

Fixed locking between fastpath and slowpath operations.

Corrected order of traffic disabling to prevent race when going down
under traffic.

- first have the microcode drop all incoming packets
- then do the slowpath stuff
- only then reset the MAC

Got rid of in_reset_task.

Remove_one() and friends would deference a null pointer if init_one
failed.

Signed-off-by: Eliezer Tamir <eliezert@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>