fix: do not fail cluster create when input dir does not contain talosconfig

As `--input-dir` flag now supports partial configs, it should not fail when there is no talosconfig in the directory.

This was the missing part in siderolabs/talos#8333.

Additionally, allow the `--cidr` flag when `--input-dir` is used - it is used even when the input configs are provided.

Signed-off-by: Utku Ozdemir <utku.ozdemir@siderolabs.com>

cmd/talosctl/cmd/mgmt/cluster/create.go

@@ -1169,7 +1169,6 @@ func checkForDefinedGenFlag(flags *pflag.FlagSet) string {
 		networkIPv4Flag,
 		networkIPv6Flag,
 		networkMTUFlag,
-		networkCIDRFlag,
 		nameserversFlag,
 		clusterDiskSizeFlag,
 		clusterDisksFlag,

pkg/machinery/config/bundle/bundle.go

@@ -85,6 +85,10 @@ func NewBundle(opts ...Option) (*Bundle, error) {
 
 		// Pull existing talosconfig
 		talosConfig, err := os.Open(filepath.Join(options.ExistingConfigs, "talosconfig"))
+		if os.IsNotExist(err) { // talosconfig is optional
+			return bundle, nil
+		}
+
 		if err != nil {
 			return bundle, err
 		}