aperture_64.c: duplicated code, buggy?

Hi!

void __init early_gart_iommu_check(void)

contains

	for (num = 24; num < 32; num++) {
		if (!early_is_k8_nb(read_pci_config(0, num, 3, 0x00)))
			continue;

loop, with very similar loop duplicated in

void __init gart_iommu_hole_init(void)

. First copy of a loop seems to be buggy, too. It uses 0 as a "nothing
set" value, which may actually bite us in last_aper_enabled case
(because it may be often zero).

(Beware, it is hard to test this patch, because this code has about
2^8 different code paths, depending on hardware and cmdline settings).

Plus, the second loop does not check for consistency of
aper_enabled. Should it?

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>