ARM: dts: stm32: lxa-tac: move adc and gpio{e,g} to gen{1,2} boards

ARM: dts: stm32: lxa-tac: move adc and gpio{e,g} to gen{1,2} boards

This is a preparation patch in order to add lxa-tac generation 3
board.

As the gen3 board has a different adc and gpio{e,g} setups, move these
from the stm32mp15xc-lxa-tac.dtsi to the gen{1,2}.dts files.

Signed-off-by: Leonard Göhrs <l.goehrs@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>