sandbox: fdt: add support for CONFIG_OF_CONTROL

This adds support for a controlling fdt, mirroring the ARM implementation.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/sandbox/lib/board.c b/arch/sandbox/lib/board.c
index b7997e9..6d464d6 100644
--- a/arch/sandbox/lib/board.c
+++ b/arch/sandbox/lib/board.c
@@ -156,6 +156,14 @@
 
 	memset((void *)gd, 0, sizeof(gd_t));
 
+#if defined(CONFIG_OF_EMBED)
+	/* Get a pointer to the FDT */
+	gd->fdt_blob = _binary_dt_dtb_start;
+#elif defined(CONFIG_OF_SEPARATE)
+	/* FDT is at end of image */
+	gd->fdt_blob = (void *)(_end_ofs + _TEXT_BASE);
+#endif
+
 	for (init_fnc_ptr = init_sequence; *init_fnc_ptr; ++init_fnc_ptr) {
 		if ((*init_fnc_ptr)() != 0)
 			hang();