stand/efi: Consolidate integer types

We have no need for 5 different copies of these.

Sponsored by: Netflix
Reviewed by: rcm, kevans, andrew
Differential Revision: https://reviews.freebsd.org/D42699

Remove $FreeBSD$: one-line .c comment pattern

Remove /^/[*/]\s*\$FreeBSD\$.*\n/

efi: switch boot_services_gone to boot_services_active

Turn the presence or absence of boot services into a positive bool (and
change its type to bool). Move declaration to efi.h in the global
variables section.

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Reviewed by: tsoome, kib
Differential Revision: https://reviews.freebsd.org/D31814

Create boot_img as a global variable

Get the information from the image that we're booting and store it in
a global variable. Prefer using this to passing it around. Remove the
special case for zfs that set the preferred boot handle by having it
uses this global variable diretly.

Reviewed by: kevans@
Differential Revision: https://reviews.freebsd.org/D20015

loader.efi: efi variable rework and lsefi command added

This update does add diag and debug capabilities to interpret the efi
variables, configuration and protocols (lsefi).

The side effect is that we add/update bunch of related headers.

libefi: UEFI_BOOT_VAR_GUID duplicates EFI_GLOBAL_VARIABLE

Drop UEFI_BOOT_VAR_GUID and use EFI_GLOBAL_VARIABLE.

Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D14696

Add GUID for UEFI boot manager variables.

Sponsoered by: Netflix

Move sys/boot to stand. Fix all references to new location

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