batman-adv: netlink: add translation table query

This adds the commands BATADV_CMD_GET_TRANSTABLE_LOCAL and
BATADV_CMD_GET_TRANSTABLE_GLOBAL, which correspond to the transtable_local
and transtable_global debugfs files.

The batadv_tt_client_flags enum is moved to the UAPI to expose it as part
of the netlink API.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[sven.eckelmann@open-mesh.com: add policy for attributes, fix includes]
Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com>
[sw@simonwunderlich.de: fix VID attributes content]
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
diff --git a/net/batman-adv/netlink.h b/net/batman-adv/netlink.h
index b399f49..52eb162 100644
--- a/net/batman-adv/netlink.h
+++ b/net/batman-adv/netlink.h
@@ -23,8 +23,11 @@
 #include <linux/types.h>
 #include <net/genetlink.h>
 
+struct nlmsghdr;
+
 void batadv_netlink_register(void);
 void batadv_netlink_unregister(void);
+int batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype);
 
 int batadv_netlink_tpmeter_notify(struct batadv_priv *bat_priv, const u8 *dst,
 				  u8 result, u32 test_time, u64 total_bytes,