atl1: do not drop rx/tx interrupts before they are scheduled

To prevent interrupts lost they should be dropped only if
they are scheduled via napi interfaces. In other case, there is
exists situation when napi handler process TX interrupt, stay in
RX processing and in that moment any other interrupt received.
Then before this patch TX bit in ISR will be cleaned, napi
schedule will not occur in case of currently processing event and
TX interrupt definitely will be lost.

Signed-off-by: Tony Zelenoff <antonz@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>