Matches ctl version to upstream

clitools/pkg/system/hostname_linux.go

@@ -0,0 +1,12 @@
+//go:build linux
+
+package system
+
+import "golang.org/x/sys/unix"
+
+func SetHostname(hostname string) error {
+	if hostname == "" {
+		return nil
+	}
+	return unix.Sethostname([]byte(hostname))
+}