bnx2x: fix logical op

Fix dubious logical operation that was found by sparse:
linux-next-20080807/drivers/net/bnx2x_main.c:7205:27: warning: dubious: !x & y

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>