bootstage: Convert to use malloc()

At present bootstage uses the data section of the image to store its
information. There are a few problems with this:

- It does not work on all boards (e.g. those which run from flash before
relocation)
- Allocated strings still point back to the pre-relocation data after
relocation

Now that U-Boot has a pre-relocation malloc() we can use this instead,
with a pointer to the data in global_data. Update bootstage to do this and
set up an init routine to allocate the memory.

Now that we have a real init function, we can drop the fake 'reset' record
and add a normal one instead.

Note that part of the problem with allocated strings remains. They are
reallocated but this will only work where pre-relocation memory is
accessible after relocation.

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

common/board_f.c

@@ -673,8 +673,14 @@ static int jump_to_copy(void)
 #endif
 
 /* Record the board_init_f() bootstage (after arch_cpu_init()) */
-static int mark_bootstage(void)
+static int initf_bootstage(void)
 {
+	int ret;
+
+	ret = bootstage_init(true);
+	if (ret)
+		return ret;
+
 	bootstage_mark_name(BOOTSTAGE_ID_START_UBOOT_F, "board_init_f");
 
 	return 0;
@@ -735,7 +741,7 @@ static const init_fnc_t init_sequence_f[] = {
 	mach_cpu_init,		/* SoC/machine dependent CPU setup */
 	initf_dm,
 	arch_cpu_init_dm,
-	mark_bootstage,		/* need timer, go after init dm */
+	initf_bootstage,		/* need timer, go after init dm */
 #if defined(CONFIG_BOARD_EARLY_INIT_F)
 	board_early_init_f,
 #endif