jme: Faulty IRQ handle bug fix

Fix IRQ handle bug when interrupt mode.

The driver was incorrectly handled and returned IRQ_HANDLED
while the device is not generating the interrupt.
It happened due to faulty determination of interrupt status register.

Found by: "Ethan" <ethanhsiao@jmicron.com>
Fixed by: "akeemting" <akeem@jmicron.com>
Signed-off-by: NGuo-Fu Tseng <cooldavid@cooldavid.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/jme.c

@@ -1463,7 +1463,7 @@ jme_intr(int irq, void *dev_id)
 	/*
 	 * Check if it's really an interrupt for us
 	 */
-	if (unlikely(intrstat == 0))
+	if (unlikely((intrstat & INTR_ENABLE) == 0))
 		return IRQ_NONE;
 
 	/*