[CmdSwitches] Add undefined cmd check

src/cmdSwitches.js

@@ -10,6 +10,7 @@ const presets = {
 module.exports = () => {
   let c = {};
   for (const x of ('base,' + (oaConfig.cmdPreset || 'perf')).split(',').reduce((a, x) => a.concat(presets[x]?.split(' ')), [])) {
+    if (!x) continue;
     const [ k, v ] = x.split('=');
 
     (c[k] = c[k] || []).push(v);