x86: Allow setup code to manage its own global data

Currently x86 has its own means of managing the global data and board data
(bd_t), and this code resides in start.S. With generic board, we need to
ensure that we leave this alone - i.e. don't clear it as we do on other
archs.

This fixes a problem where the memory init data is cleared which causes
the video driver to operate very slowly.

Signed-off-by: Simon Glass <sjg@chromium.org>

common/board_f.c

@@ -755,7 +755,7 @@ static int mark_bootstage(void)
 static init_fnc_t init_sequence_f[] = {
 #if !defined(CONFIG_CPM2) && !defined(CONFIG_MPC512X) && \
 		!defined(CONFIG_MPC83xx) && !defined(CONFIG_MPC85xx) && \
-		!defined(CONFIG_MPC86xx)
+		!defined(CONFIG_MPC86xx) && !defined(CONFIG_X86)
 	zero_global_data,
 #endif
 	setup_fdt,

common/board_r.c

@@ -721,9 +721,6 @@ init_fnc_t init_sequence_r[] = {
 	 */
 #ifdef CONFIG_CLOCKS
 	set_cpu_clk_info, /* Setup clock information */
-#endif
-#ifdef CONFIG_X86
-	init_bd_struct_r,
 #endif
 	initr_reloc_global_data,
 	initr_serial,