Remove unnecessary Darwin helpers. (project-chip#1455)

These were just added, but it turns out they are not actually needed.

src-electron/generator/matter/darwin/Framework/CHIP/templates/helper.js

@@ -1259,25 +1259,6 @@ async function async_not(value) {
   return !toBeNegated;
 }
 
-function isLessThan(value1, value2) {
-  return value1 < value2;
-}
-
-function stripPrefix(value, prefix) {
-  if (value.startsWith(prefix)) {
-    return value.substring(prefix.length);
-  }
-
-  return value;
-}
-
-function cleanDeviceName(deviceName) {
-  deviceName = stripPrefix.call(this, deviceName, 'Matter ');
-  return appHelper.asUpperCamelCase.call(this, deviceName, {
-    hash: { preserveAcronyms: true }
-  });
-}
-
 //
 // Module exports
 //
@@ -1312,9 +1293,6 @@ exports.async_not = async_not;
 exports.oldName = oldName;
 exports.hasOldName = hasOldName;
 exports.hasRenamedFields = hasRenamedFields;
-exports.isLessThan = isLessThan;
-exports.stripPrefix = stripPrefix;
-exports.cleanDeviceName = cleanDeviceName;
 
 exports.meta = {
   category: dbEnum.helperCategory.matter,