drivers: adc: stm32U5 channel preselection
drivers: adc: stm32U5 channel preselection

The stm32U5 LL function name differs from stm32H7 serie but must
still be enabled in the PCSEL.
This is done with the LL_ADC_SetChannelPreselection function
until the LL changes its name.

Signed-off-by: Francois Ramu <b83adc7f8a23ee911a37fcb61c4033581aae0b7a@st.com>

finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr