bnx2: Need to call cnic_setup_cnic_irq_info() after MTU change.

New status blocks are allocated during MTU change so we need to
update this information for the cnic driver.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>