[botanist] Improve IP debugging information.

Change-Id: I4811f956a7ca926d7837692e3a56d5b96773e442
diff --git a/cmd/botanist/run.go b/cmd/botanist/run.go
index cd549c1..5d2b558 100644
--- a/cmd/botanist/run.go
+++ b/cmd/botanist/run.go
@@ -150,8 +150,10 @@
 	}
 
 	ip, err := botanist.ResolveIPv4(ctx, nodename, netstackTimeout)
-	if err != nil {
-		logger.Errorf(ctx, "could not resolve IP address: %v", err)
+	if err == nil {
+		logger.Infof(ctx, "IPv4 address of %s found: %s", nodename, ip)
+	} else {
+		logger.Errorf(ctx, "could not resolve IPv4 address of %s: %v", nodename, err)
 	}
 
 	env := append(