net: stmmac: dwmac4: mac address array boudary violation issue

The mac address array size is GMAC_MAX_PERFECT_ADDRESSES,
so the 'reg' should be less than it, or will affect other registers.
Signed-off-by: Biao Huang <biao.huang@mediatek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c

@@ -454,7 +454,7 @@ static void dwmac4_set_filter(struct mac_device_info *hw,
 			reg++;
 		}
 
-		while (reg <= GMAC_MAX_PERFECT_ADDRESSES) {
+		while (reg < GMAC_MAX_PERFECT_ADDRESSES) {
 			writel(0, ioaddr + GMAC_ADDR_HIGH(reg));
 			writel(0, ioaddr + GMAC_ADDR_LOW(reg));
 			reg++;