Pull EFI fixes from Ingo Molnar:
"This contains a Xen fix, an arm64 fix and a race condition /
robustization set of fixes related to ExitBootServices() usage and
boundary conditions"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Use efi_exit_boot_services()
efi/libstub: Use efi_exit_boot_services() in FDT
efi/libstub: Introduce ExitBootServices helper
efi/libstub: Allocate headspace in efi_get_memory_map()
efi: Fix handling error value in fdt_find_uefi_params
efi: Make for_each_efi_memory_desc_in_map() cope with running on Xen