dts: arm: st: l5: add stm32l552xc dtsi file

This dts include file is for certain stm32 boards
such as the stm32l552zc,which have a memory size
of 256KB for both flash and RAM peripherals.

Signed-off-by: Fabrice DJIATSA <fabrice.djiatsa-ext@st.com>

Author: djiatsaf-st

dts/arm/st/l5/stm32l552Xc.dtsi

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2025 STMicroelectronics
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <mem.h>
+#include <st/l5/stm32l552.dtsi>
+
+/ {
+	sram0: memory@20000000 {
+		reg = <0x20000000 DT_SIZE_K(256)>;
+	};
+
+	soc {
+		flash-controller@40022000 {
+			flash0: flash@8000000 {
+				reg = <0x08000000 DT_SIZE_K(256)>;
+			};
+		};
+	};
+};