driver: add new allowedip flag

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Author: zx2c4

driver/configuration_windows.go

@@ -20,11 +20,17 @@ const (
 	AdapterStateUp   AdapterState = 1
 )
 
+type AllowedIpFlag uint32
+
+const (
+	AllowedIpRemove AllowedIpFlag = 1 << 0
+)
+
 type AllowedIP struct {
 	Address       [16]byte
 	AddressFamily winipcfg.AddressFamily
 	Cidr          uint8
-	_             [4]byte
+	Flags         AllowedIpFlag
 }
 
 type PeerFlag uint32