arch: microblaze: Weak sys_arch_reboot implementation

Internal references: FWRIVERHD-4554

Signed-off-by: Alp Sayin <alpsayin@gmail.com>

Author: alpsayin

arch/microblaze/core/reboot.c

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2023 Advanced Micro Devices, Inc. (AMD)
+ * Copyright (c) 2023 Alp Sayin <alpsayin@gmail.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/arch/cpu.h>
+#include <zephyr/kernel.h>
+#include <zephyr/sys/util.h>
+
+/**
+ * @brief Reset the system
+ *
+ * This is stub function to avoid build error with CONFIG_REBOOT=y
+ * MicroBlaze, being a soft core cannot define a reboot routine.
+ * Each SoC designer should implement their own reboot if needed.
+ */
+
+void __weak sys_arch_reboot(int type)
+{
+	printk("__weak reboot called with %d in %s\n", type, __FILE__);
+	__asm__ volatile("\tbraid _start\n"
+			 "\tmts rmsr, r0\n");
+}