lib: utils: Add simple FDT based system suspend driver framework

The generic platform can have multiple system suspend drivers so add a
simple FDT based system suspend driver framework.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>

lib/utils/suspend/fdt_suspend.c

@@ -0,0 +1,22 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2024 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ *   Anup Patel <apatel@ventanamicro.com>
+ */
+
+#include <sbi_utils/suspend/fdt_suspend.h>
+
+/* List of FDT suspend drivers generated at compile time */
+extern const struct fdt_driver *const fdt_suspend_drivers[];
+
+void fdt_suspend_init(const void *fdt)
+{
+	/*
+	 * Platforms might have multiple system suspend devices or
+	 * might not have any so probe all and don't fail.
+	 */
+	fdt_driver_init_all(fdt, fdt_suspend_drivers);
+}