tests: adc_api: Add xmc45_relax_kit config

Adds xmc45_relax_kit configuration.

Signed-off-by: Andriy Gelman <[email protected]>

Author: talih0

tests/drivers/adc/adc_api/boards/xmc45_relax_kit.overlay

@@ -0,0 +1,3 @@
+&adc0 {
+	status = "okay";
+};

tests/drivers/adc/adc_api/src/test_adc.c

@@ -384,6 +384,16 @@
 #define ADC_1ST_CHANNEL_ID	0
 #define ADC_2ND_CHANNEL_ID	1
 
+#elif defined(CONFIG_BOARD_XMC45_RELAX_KIT)
+
+#define ADC_DEVICE_NODE		DT_INST(0, infineon_xmc4xxx_adc)
+#define ADC_RESOLUTION		12
+#define ADC_GAIN		ADC_GAIN_1
+#define ADC_REFERENCE		ADC_REF_INTERNAL
+#define ADC_ACQUISITION_TIME	ADC_ACQ_TIME_DEFAULT
+#define ADC_1ST_CHANNEL_ID	0
+#define ADC_2ND_CHANNEL_ID	1
+
 #else
 #error "Unsupported board."
 #endif