Fix ADC config gating: use io_channels property and add length validation

Co-authored-by: soburi <458281+soburi@users.noreply.github.com>

Author: Copilot

cores/arduino/zephyrCommon.cpp

@@ -293,7 +293,7 @@ size_t pwm_pin_index(pin_size_t pinNumber) {
 		    ())
 
 const struct adc_dt_spec arduino_adc[] = {
-#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), adc_pin_gpios)
+#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), io_channels)
   DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), io_channels, ADC_DT_SPEC)
 #elif defined(ZARD_ADC_CONNECTOR)
   DT_FOREACH_MAP_ENTRY(DT_NODELABEL(ZARD_ADC_CONNECTOR), io_channel_map, ADC_CONN_CHANNEL_DT)
@@ -310,13 +310,21 @@ const pin_size_t arduino_analog_pins[] = {
 };
 
 struct adc_channel_cfg channel_cfg[ARRAY_SIZE(arduino_analog_pins)] = {
-#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), adc_pin_gpios)
+#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), io_channels)
   DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), io_channels, ADC_CH_CFG)
 #elif defined(ZARD_ADC_CONNECTOR)
   DT_FOREACH_MAP_ENTRY(DT_NODELABEL(ZARD_ADC_CONNECTOR), io_channel_map, ADC_CONN_CHANNEL_CFG)
 #endif
 };
 
+#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), io_channels) && \
+    DT_NODE_HAS_PROP(DT_PATH(zephyr_user), adc_pin_gpios)
+#if DT_PROP_LEN(DT_PATH(zephyr_user), io_channels) != \
+    DT_PROP_LEN(DT_PATH(zephyr_user), adc_pin_gpios)
+#error "io_channels and adc_pin_gpios must have the same length"
+#endif
+#endif
+
 size_t analog_pin_index(pin_size_t pinNumber) {
   for(size_t i=0; i<ARRAY_SIZE(arduino_analog_pins); i++) {
     if (arduino_analog_pins[i] == pinNumber) {