sh: add support for linking a builtin device tree blob in the kernel

Signed-off-by: Rich Felker <dalias@libc.org>

arch/sh/kernel/setup.c

@@ -251,7 +251,11 @@ void __ref sh_fdt_init(phys_addr_t dt_phys)
 	/* Avoid calling an __init function on secondary cpus. */
 	if (done) return;
 
+#ifdef CONFIG_USE_BUILTIN_DTB
+	dt_virt = __dtb_start;
+#else
 	dt_virt = phys_to_virt(dt_phys);
+#endif
 
 	if (!dt_virt || !early_init_dt_scan(dt_virt)) {
 		pr_crit("Error: invalid device tree blob"