Add support to toggle "Always Show Data RAT Icon"

[ThePhoenix576]

Hey, so I figured out that in Android they have some icons toggle for showing RAT even when idle. Apparently with Shizuku you can toggle it to be turned on. Like in another app called Pixel IMS. Is it possible for SystemUI Tuner to also toggle these UI modifications?

Android docs page : https://developer.android.com/reference/android/telephony/CarrierConfigManager#KEY_ALWAYS_SHOW_DATA_RAT_ICON_BOOL
App that uses Shizuku that can toggle the boolean to always show it : https://github.com/kyujin-cho/pixel-volte-patch/

Here is an example that I got from other people using this app to toggle the option to always show the RAT icons