Updated list command to handle errors

adsb/src/main.rs

@@ -49,7 +49,8 @@ fn main() -> Result<()> {
   }
   // List devices
   else if args.list {
-    RtlSdrDevice::list()
+    RtlSdrDevice::list();
+    Ok(())
   }
   // Handle decode mode
   else if let Some(mut hex_string) = args.decode {