this is mainly to avoid panics due to improper accounting at insmod and rmmod
should be fixed in future.

required for the case when txq times out and nic unloads and reloads.
it tries to free up all pkts queued between prod and cons. some of
these maybe our special dummy pkt, which should not be freed until
rmmod.

disabled for now, since the current code still seems to work fine.

do update_fpsb_idx from hw irq handler before re-enabling NIC INTR, and do not
run this update function from bnx2x_poll while we are running our enforcement
module. this seems to reduce the number of hw interrupts generated, since now
the NIC does not think that the previous set of pkts have not been acknowledged
by the driver.