tests,samples: boards: espressif: add missing psram0 node

Add missing psram0 node which is used to determine the memory size.

Signed-off-by: Marek Matej <[email protected]>

Author: marekmatej

samples/boards/espressif/spiram_test/app.overlay

@@ -0,0 +1,10 @@
+/*
+ * Copyright (c) 2025 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/* Using the smallest available PSRAM size of 2MB */
+&psram0 {
+	size = <DT_SIZE_M(2)>;
+};

tests/boards/espressif/cache_coex/app.overlay

@@ -0,0 +1,10 @@
+/*
+ * Copyright (c) 2025 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/* Using the smallest available PSRAM size of 2MB */
+&psram0 {
+	size = <DT_SIZE_M(2)>;
+};