boards: st: vbat node enabled without enabling associated adc node

[ycsin]

Describe the bug
The ST vbat driver expects the adc node to be enabled in the devicetree (due to the usage of DEVICE_DT_GET), but the vbat nodes in multiple boards are currently being enabled without also enabling its associated adc node

zephyr/drivers/sensor/st/stm32_vbat/stm32_vbat.c

Lines 119 to 123 in adeb19b

	#define STM32_VBAT_DEFINE(inst) \
	static struct stm32_vbat_data stm32_vbat_dev_data_##inst = { \
	.adc = DEVICE_DT_GET(DT_INST_IO_CHANNELS_CTLR(inst)), \
	.adc_base = (ADC_TypeDef *)DT_REG_ADDR(DT_INST_IO_CHANNELS_CTLR(0)), \
	.adc_cfg = { \

this causes compilation to fail when vbat driver met its Kconfig conditions to build

zephyr/drivers/sensor/st/stm32_vbat/Kconfig

Lines 6 to 13 in adeb19b

	config STM32_VBAT
	bool "STM32 Vbat Sensor"
	default y
	depends on DT_HAS_ST_STM32_VBAT_ENABLED
	depends on SOC_FAMILY_STM32 && !SOC_SERIES_STM32F1X
	select ADC
	help
	Enable driver for STM32 Vbat sensor and then also ADC

To Reproduce
Steps to reproduce the behavior:

1. west build -b nucleo_h753zi -p auto zephyr/samples/sensor/sensor_shell

Expected behavior
vbat probably shouldn't be enabled if the adc that it is using isn't enabled

Impact
Causing CI to fail in #72833

Logs and console output
See 72910

Environment (please complete the following information):

• OS: Linux
• Toolchain: 0.16.5-1
• Commit SHA or Version used: main branch

Additional context
The proposed fix in #72911 only fixes the driver side of the issues, the vbat nodes are still being enabled in boards where it shouldnt

[FRASTM]

@ycsin
Adding a depends on DT_HAS_ST_STM32_ADC_ENABLED condition in the Kconfig for the drivers/sensor/st/stm32_xxx
will make the compilation successful but application is meaningless if no ADC node is enabled

[ycsin]

@ycsin Adding a depends on DT_HAS_ST_STM32_ADC_ENABLED condition in the Kconfig for the drivers/sensor/st/stm32_xxx will make the compilation successful but application is meaningless if no ADC node is enabled

The boards either fail to build the test in main branch's CI and fail, or becomes meaningless. I chose the latter as it seems less evil (and unblocks my PRs).

#72911 fixes half of the issue, the other half IMHO is to disable the vbat nodes in the board dts that are 'enabled' without an adc, or enable the adc properly with the correct configurations.

If there's usually only one vbat, maybe?:

#if !IS_ENABLED(DT_NODE_HAS_STATUS(DT_INST_IO_CHANNELS_CTLR(0), okay))
#warning "No ADC enabled for vbat 0"
#endif

[FRASTM]

If there's usually only one vbat, maybe?:

#if !IS_ENABLED(DT_NODE_HAS_STATUS(DT_INST_IO_CHANNELS_CTLR(0), okay))
#warning "No ADC enabled for vbat 0"
#endif

I Agree, with #warning or #error "No ADC node enabled"