x86: fixes some bugs about EFI memory map handling

This patch fixes some bugs of EFI memory handing code.

- On x86_64, it is possible that EFI memory map can not be mapped via
  identity map, so efi_map_memmap is removed, just use early_ioremap.

- On i386, the EFI memory map mapping take effect cross paging_init,
  so it is not necessary to use efi_map_memmap.

- EFI memory map is unmapped in efi_enter_virtual_mode to avoid
  early_ioremap leak.

Signed-off-by: Huang Ying <ying.huang@intel.com>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
index 4ccad18..697533e 100644
--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -378,10 +378,8 @@
        acpi_reserve_bootmem();
 #endif
 
-	if (efi_enabled) {
-		efi_map_memmap();
+	if (efi_enabled)
 		efi_reserve_bootmem();
-	}
 
        /*
 	* Find and reserve possible boot-time SMP configuration: