headers, net: Use __kernel_sa_family_t in more definitions shared with userland

Complete the work started with commit
6602a4baf4d1a73cc4685a39ef859e1c5ddf654c ('net: Make userland include
of netlink.h more sane').

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/ipx.h b/include/linux/ipx.h
index aabb1d2..3d48014 100644
--- a/include/linux/ipx.h
+++ b/include/linux/ipx.h
@@ -7,7 +7,7 @@
 #define IPX_MTU		576
 
 struct sockaddr_ipx {
-	sa_family_t	sipx_family;
+	__kernel_sa_family_t sipx_family;
 	__be16		sipx_port;
 	__be32		sipx_network;
 	unsigned char 	sipx_node[IPX_NODE_LEN];