rxrpc: Remove error from struct rxrpc_skb_priv as it is unused

Remove error from struct rxrpc_skb_priv as it is no longer used.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index fd64a2b..141c145 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -145,7 +145,6 @@
 	};
 	union {
 		int		remain;		/* amount of space remaining for next write */
-		u32		error;		/* network error code */
 	};
 
 	struct rxrpc_host_header hdr;		/* RxRPC packet header from this packet */