Add display resolution options to Power saving mode

[Goel]

I am currently enjoying the One UI 3.0 Beta but one very useful feature which was present in the previous power saving mode options was having the option to change the display resolution (HD+, FHD+, WQHD+) directly. 

I like it now that there is no waiting time between switching power saving options but it would be great to configure the display resolution quickly than having to open the phone settings.

[MartynaK]

@Goel,

I am glad to hear that you're enjoying our Beta Program and thanks for this idea! 😉 I'll make sure your suggestion goes to our development department! 😊