x86: fix ioremap RAM check

	if (phys_addr >= ISA_START_ADDRESS && last_addr < ISA_END_ADDRESS)

		return (__force void __iomem *)phys_to_virt(phys_addr);

#ifdef CONFIG_X86_32

	/*

	 * Don't allow anybody to remap normal RAM that we're using..

	 */

	if (phys_addr <= virt_to_phys(high_memory - 1)) {

		char *t_addr, *t_end;

		struct page *page;

		t_addr = __va(phys_addr);

		t_end = t_addr + (size - 1);

		for (page = virt_to_page(t_addr);

		     page <= virt_to_page(t_end); page++)

			if (!PageReserved(page))

	for (offset = phys_addr >> PAGE_SHIFT; offset < max_pfn_mapped &&

	     (offset << PAGE_SHIFT) < last_addr; offset++) {

		if (page_is_ram(offset))

			return NULL;

	}

#endif

	pgprot = MAKE_GLOBAL(__PAGE_KERNEL | flags);