sr9800: Check for supported Wake-on-LAN modes

The driver currently silently accepts unsupported Wake-on-LAN modes
(other than WAKE_PHY or WAKE_MAGIC) without reporting that to the user,
which is confusing.

Fixes: 19a38d8e ("USB2NET : SR9800 : One chip USB2.0 USB2NET SR9800 Device Driver Support")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/sr9800.c

@@ -421,6 +421,9 @@ sr_set_wol(struct net_device *net, struct ethtool_wolinfo *wolinfo)
 	struct usbnet *dev = netdev_priv(net);
 	u8 opt = 0;
 
+	if (wolinfo->wolopts & ~(WAKE_PHY | WAKE_MAGIC))
+		return -EINVAL;
+
 	if (wolinfo->wolopts & WAKE_PHY)
 		opt |= SR_MONITOR_LINK;
 	if (wolinfo->wolopts & WAKE_MAGIC)