x86: clean up the page table dumper and add 32-bit support

Clean up the page table dumper (fix boundary conditions, table driven
address ranges, some formatting changes since it is no longer using
the kernel log but a separate virtual file), and generalize to 32
bits.

[ mingo@elte.hu: x86: fix the pagetable dumper ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/Kconfig.debug

@@ -56,7 +56,7 @@ config DEBUG_PER_CPU_MAPS
 
 config X86_PTDUMP
 	bool "Export kernel pagetable layout to userspace via debugfs"
-	depends on X86_64
+	depends on DEBUG_KERNEL
 	select DEBUG_FS
 	help
 	  Say Y here if you want to show the kernel pagetable layout in a

arch/x86/mm/Makefile

@@ -3,6 +3,7 @@ obj-y	:=  init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o
 obj-$(CONFIG_X86_32)		+= pgtable_32.o
 
 obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o
+obj-$(CONFIG_X86_PTDUMP)	+= dump_pagetables.o
 
 obj-$(CONFIG_HIGHMEM)		+= highmem_32.o
 
@@ -12,5 +13,4 @@ else
 obj-$(CONFIG_NUMA)		+= numa_64.o
 obj-$(CONFIG_K8_NUMA)		+= k8topology_64.o
 obj-$(CONFIG_ACPI_NUMA)		+= srat_64.o
-obj-$(CONFIG_X86_PTDUMP)	+= dump_pagetables.o
 endif