m/n/c/network: fix handling of nameserver parse failure

If parsing failed, don't append the IP to the list.

Change-Id: Ie2fa2812790a919697458ec178b475a420417f6f
Reviewed-on: https://review.monogon.dev/c/monogon/+/2924
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
Tested-by: Jenkins CI
Vouch-Run-CI: Lorenz Brun <lorenz@monogon.tech>
diff --git a/metropolis/node/core/network/static.go b/metropolis/node/core/network/static.go
index 5cec110..a178e2c 100644
--- a/metropolis/node/core/network/static.go
+++ b/metropolis/node/core/network/static.go
@@ -150,6 +150,7 @@
 		nsIP := net.ParseIP(ns.Ip)
 		if nsIP == nil {
 			l.Warningf("failed to parse %q as nameserver IP", ns.Ip)
+			continue
 		}
 		nsIPList = append(nsIPList, nsIP)
 	}