inet: raw -- Reserve image members for sockets options

In vz7 we've a slightly different code base where fields
2 and 3 are already used. So lets reserve them and move
raw member to another number.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>

images/sk-inet.proto

@@ -13,7 +13,8 @@ message ip_opts_raw_entry {
 
 message ip_opts_entry {
 	optional bool			freebind	= 1;
-	optional ip_opts_raw_entry	raw		= 2;
+	// Fields 2 and 3 are reserved for vz7 use
+	optional ip_opts_raw_entry	raw		= 4;
 }
 
 message inet_sk_entry {