CEC: Remove the TODO in HdmiPlaybackClient class

HdmiControlService.oneTouchPlay method is already switching the
long running one touch play process to the service thread from
the UI thread and is also able to handle multiple OTP requests
in parallel. Remove TODO to use PendingResult.

Bug: 159901363
Test: None
Change-Id: Ife8c8268edb8a40255a52dd1eda2ab60020803c8

core/java/android/hardware/hdmi/HdmiPlaybackClient.java

@@ -84,7 +84,6 @@ public final class HdmiPlaybackClient extends HdmiClient {
      *         of the result
      */
     public void oneTouchPlay(OneTouchPlayCallback callback) {
-        // TODO: Use PendingResult.
         try {
             mService.oneTouchPlay(getCallbackWrapper(callback));
         } catch (RemoteException e) {