Control files for some OnePlus devices

[Blue-Sauce]

For Oneplus Nord running Android 12, Oneplus Nord n200.
/sys/devices/virtual/oplus_chg/battery/mmi_charging_enable Enabled value: 1, Disabled value 0

For Oneplus 7T Pro running Android 12
/sys/class/power_supply/battery/mmi_charging_enable Enabled value: 1, Disabled value 0

May work on other OnePlus devices

[inmaldrerah]

The former also works for Oneplus Ace 2 (and probably 11R).