Handle the RX FIFO overflow condition with the rxeof handler instead

of the rxeoc handler for now. The rxeoc handler will reset the link,
and the NatSemi chip's RX FIFO will overflow on a 32-bit bus once you
start hitting it with 500Mbps or more of traffic.

Also increase the size of the RX ring to 128 descriptors (was 64).

sys/dev/nge/if_nge.c

@@ -1495,12 +1495,13 @@ static void nge_intr(arg)
 
 		if ((status & NGE_ISR_RX_DESC_OK) ||
 		    (status & NGE_ISR_RX_ERR) ||
+		    (status & NGE_ISR_RX_OFLOW) ||
 		    (status & NGE_ISR_RX_OK))
 			nge_rxeof(sc);
-
+#ifdef notdef
 		if ((status & NGE_ISR_RX_OFLOW))
 			nge_rxeoc(sc);
-
+#endif
 		if (status & NGE_ISR_SYSERR) {
 			nge_reset(sc);
 			ifp->if_flags &= ~IFF_RUNNING;

sys/dev/nge/if_ngereg.h

@@ -562,7 +562,7 @@ struct nge_desc_32 {
 #define NGE_RXEXTSTS_UDPPKT	0x00200000
 #define NGE_RXEXTSTS_UDPCSUMERR	0x00400000
 
-#define NGE_RX_LIST_CNT		64
+#define NGE_RX_LIST_CNT		128
 #define NGE_TX_LIST_CNT		128
 
 struct nge_list_data {