CONFIG_ZMK_BATTERY_NRF_VDDH and CONFIG_ZMK_BATTERY_VOLTAGE_DIVIDER are
now automatically enabled if a DT node with the matching "compatible"
property is present and enabled, so they no longer need to be manually
set for each board.
battery.c now uses the zmk,battery chosen node to select a battery
sensor. Using the node labeled "BATTERY" is maintained for backwards
compatibility but is now deprecated. Custom boards should switch to
using the chosen node.
# Conflicts:
# app/boards/arm/bluemicro840/bluemicro840_v1.dts
# app/boards/arm/nice60/nice60.dts
# app/boards/arm/nrfmicro/nrfmicro_13.dts
# Conflicts:
# app/boards/arm/bluemicro840/bluemicro840_v1.dts
