x86: Add an fdt pointer to the global data structure

This change adds a pointer to the global data structure in x86 to point to
the device tree. This mirrors an identical pointer in ARM.
Signed-off-by: NGabe Black <gabeblack@chromium.org>
Signed-off-by: NSimon Glass <sjg@chromium.org>

arch/x86/include/asm/global_data.h

@@ -58,6 +58,7 @@ struct global_data {
 	unsigned long	gdt_addr;	/* Location of GDT */
 	phys_size_t	ram_size;	/* RAM size */
 	unsigned long	reset_status;	/* reset status register at boot */
+	const void	*fdt_blob;	/* Our device tree, NULL if none */
 	void		**jt;		/* jump table */
 	char		env_buf[32];	/* buffer for getenv() before reloc. */
 };