lib/util: Fix build on old versions of libbpf without XDP feature flag support

The build errors out with old libbpf versions because the ifdef'ed
version of iface_get_xdp_feature_flags() doesn't use any of its
arguments. Change the ifdef'ed version to mark the arguments as __unused
to avoid this.

Signed-off-by: Toke Høiland-Jørgensen <[email protected]>

Author: tohojo

lib/util/util.c

@@ -864,9 +864,9 @@ int iface_print_status(const struct iface *iface)
 	return err;
 }
 
+#ifdef HAVE_LIBBPF_BPF_XDP_QUERY
 int iface_get_xdp_feature_flags(int ifindex, __u64 *feature_flags)
 {
-#ifdef HAVE_LIBBPF_BPF_XDP_QUERY
 	LIBBPF_OPTS(bpf_xdp_query_opts, opts);
 	int err;
 
@@ -876,8 +876,10 @@ int iface_get_xdp_feature_flags(int ifindex, __u64 *feature_flags)
 
 	*feature_flags = opts.feature_flags;
 	return 0;
+}
 #else
+int iface_get_xdp_feature_flags(__unused int ifindex, __unused __u64 *feature_flags)
+{
 	return -EOPNOTSUPP;
-#endif
-
 }
+#endif