Change in coreboot[master]: libpayload: Add mock architecture

[Jakub Czapiga (Code Review)]

Attention is currently required from: Jakub Czapiga, Paul Menzel, Jan Dabros.
Hello build bot (Jenkins), Julius Werner, Jan Dabros, Yu-Ping Wu,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/57708

to look at the new patch set (#9).

Change subject: libpayload: Add mock architecture
......................................................................

libpayload: Add mock architecture

Mock architecture can be used to build libpayload using host compiler.
It can be enabled by setting ARCH_MOCK=y in the dotconfig. It sets
LITTLE_ENDIAN=y, as most machines these days use little-endian CPUs.
Libpayload will use HOSTCC as CC, HOSTLD as LD, etc. instead of tools
provided by xcompile.
Mock architecture configuration can be used by payloads for testing
purposes. Thanks to it, tests can be architecture-independent,
and can be executed without requiring compatible Kconfig options,
e.g. ARCH_ARM64=y for ARM64 machine. However, one has to provide
implementation for most architecture-specific functions present
in arch/* directories.

Signed-off-by: Jakub Czapiga 
Change-Id: Ie3a6e6f6cad2f8a2e48a8e546d3b79c577653080
---
M payloads/libpayload/Kconfig
M payloads/libpayload/Makefile
M payloads/libpayload/Makefile.inc
A payloads/libpayload/arch/mock/Kconfig
A payloads/libpayload/arch/mock/Makefile.inc
A payloads/libpayload/arch/mock/head.c
A payloads/libpayload/arch/mock/libpayload.ldscript
A payloads/libpayload/arch/mock/mock_media.c
A payloads/libpayload/arch/mock/virtual.c
M payloads/libpayload/bin/lpgcc
A payloads/libpayload/include/mock/arch/barrier.h
A payloads/libpayload/include/mock/arch/cache.h
A payloads/libpayload/include/mock/arch/io.h
A payloads/libpayload/include/mock/arch/types.h
A payloads/libpayload/include/mock/arch/virtual.h
M payloads/libpayload/sample/Makefile
A payloads/libpayload/sample/arch_mock/Makefile
A payloads/libpayload/sample/arch_mock/hello.c
A payloads/libpayload/sample/arch_mock/hello_mocks.c
19 files changed, 329 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/08/57708/9