fix: LiXee ZLinky: handle empty TIC command list

If the user defines a value for tic_command_whitelist and then clears
it, it remains in the configuration as an empty string.
An empty string should be the same as no value at all. Before this
change, when the string was empty, no attributes were polled.

Let's also suggest a Z2M restart in the description, it's the easiest way to
restart the poll.

Author: sbraz

src/devices/lixee.ts

@@ -1746,7 +1746,7 @@ function getCurrentConfig(device: Zh.Device, options: KeyValue) {
     }
 
     // Filter exposed attributes with user whitelist
-    if (options?.tic_command_whitelist != null) {
+    if (options?.tic_command_whitelist) {
         // @ts-expect-error ignore
         const tic_commands_str = options.tic_command_whitelist.toUpperCase();
         if (tic_commands_str !== "ALL") {
@@ -1811,7 +1811,7 @@ export const definitions: DefinitionWithExtend[] = [
                 ),
             e
                 .text("tic_command_whitelist", ea.SET)
-                .withDescription("List of TIC commands to be exposed (separated by comma). Reconfigure device after change. Default: all"),
+                .withDescription("List of TIC commands to be exposed (separated by comma). Requires Z2M restart. Default: all"),
         ],
         configure: async (device, coordinatorEndpoint) => {
             const endpoint = device.getEndpoint(1);