x86: Add support for booting Linux using the 32 bit boot protocol

This change conditionally modifies the zboot command so that it can use the
32 bit boot protocol. This is necessary because the 16 bit realmode entry
point assumes that it can call BIOS services which neither coreboot nor
u-boot provide.

Signed-off-by: Gabe Black <gabeblack@chromium.org>
diff --git a/arch/x86/lib/bootm.c b/arch/x86/lib/bootm.c
index bac7b4f..ba3875b 100644
--- a/arch/x86/lib/bootm.c
+++ b/arch/x86/lib/bootm.c
@@ -38,6 +38,7 @@
 	void		*base_ptr = NULL;
 	ulong		os_data, os_len;
 	image_header_t	*hdr;
+	void		*load_address;
 
 #if defined(CONFIG_FIT)
 	const void	*data;
@@ -75,7 +76,8 @@
 
 #ifdef CONFIG_CMD_ZBOOT
 	base_ptr = load_zimage((void *)os_data, os_len,
-			images->rd_start, images->rd_end - images->rd_start, 0);
+			images->rd_start, images->rd_end - images->rd_start,
+			0, &load_address);
 #endif
 
 	if (NULL == base_ptr) {
@@ -92,7 +94,7 @@
 	/* we assume that the kernel is in place */
 	printf("\nStarting kernel ...\n\n");
 
-	boot_zimage(base_ptr);
+	boot_zimage(base_ptr, load_address);
 	/* does not return */
 
 error: