tests: drivers: adc: adc_api: update adc_api test

-add nucleo_u385rg_q overlays files
for testbench purpose.
- add platform_exclude property to skip test on boards
with little ram size.

Signed-off-by: Khaoula Bidani <[email protected]>

Author: kbidani

tests/drivers/adc/adc_api/boards/nucleo_u385rg_q.overlay

@@ -0,0 +1,25 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Copyright (c) 2025 STMicroelectronics
+ */
+
+/ {
+	zephyr,user {
+		/* adjust channel number according to pinmux in board.dts */
+		io-channels = <&adc1 1>;
+	};
+};
+
+&adc1 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	channel@1 {
+		reg = <1>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+};

tests/drivers/adc/adc_api/testcase.yaml

@@ -51,6 +51,7 @@ tests:
       - nucleo_l152re
       - nucleo_l476rg
       - nucleo_u083rc
+      - nucleo_u385rg_q
       - nucleo_u575zi_q
       - nucleo_wb55rg
       - nucleo_wba55cg