alx: make sizes unsigned

The ring sizes should be unsigned, pointed out by Ben Hutchings.

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/atheros/alx/alx.h b/drivers/net/ethernet/atheros/alx/alx.h
index 50b3ae2..d71103d 100644
--- a/drivers/net/ethernet/atheros/alx/alx.h
+++ b/drivers/net/ethernet/atheros/alx/alx.h
@@ -85,16 +85,16 @@
 	struct {
 		dma_addr_t dma;
 		void *virt;
-		int size;
+		unsigned int size;
 	} descmem;
 
 	/* protect int_mask updates */
 	spinlock_t irq_lock;
 	u32 int_mask;
 
-	int tx_ringsz;
-	int rx_ringsz;
-	int rxbuf_size;
+	unsigned int tx_ringsz;
+	unsigned int rx_ringsz;
+	unsigned int rxbuf_size;
 
 	struct napi_struct napi;
 	struct alx_tx_queue txq;