wireguard: skip peer config if public key of the peer is not defined

If a config section of a peer does not have a public key defined, the
whole interface does not start. The following log is shown

daemon.notice netifd: test (21071): Line unrecognized: `PublicKey='
daemon.notice netifd: test (21071): Configuration parsing erro

The command 'wg show' does only show the interface name.

With this change we skip the peer for this interface and emit a log
message. So the other peers get configured.

Signed-off-by: Florian Eckert <fe@dev.tdt.de>

package/network/utils/wireguard-tools/files/wireguard.sh

@@ -42,6 +42,11 @@ proto_wireguard_setup_peer() {
 	config_get endpoint_port "${peer_config}" "endpoint_port"
 	config_get persistent_keepalive "${peer_config}" "persistent_keepalive"
 
+	if [ -z "$public_key" ]; then
+		echo "Skipping peer config $peer_config because public key is not defined."
+		return 0
+	fi
+
 	echo "[Peer]" >> "${wg_cfg}"
 	echo "PublicKey=${public_key}" >> "${wg_cfg}"
 	if [ "${preshared_key}" ]; then