treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests/powerpc: Fix Makefiles for headers_install change

Commit b2d35fa5fc80 ("selftests: add headers_install to lib.mk")
introduced a requirement that Makefiles more than one level below the
selftests directory need to define top_srcdir, but it didn't update
any of the powerpc Makefiles.

This broke building all the powerpc selftests with eg:

make[1]: Entering directory '/src/linux/tools/testing/selftests/powerpc'
BUILD_TARGET=/src/linux/tools/testing/selftests/powerpc/alignment; mkdir -p $BUILD_TARGET; make OUTPUT=$BUILD_TARGET -k -C alignment all
make[2]: Entering directory '/src/linux/tools/testing/selftests/powerpc/alignment'
../../lib.mk:20: ../../../../scripts/subarch.include: No such file or directory
make[2]: *** No rule to make target '../../../../scripts/subarch.include'.
make[2]: Failed to remake makefile '../../../../scripts/subarch.include'.
Makefile:38: recipe for target 'alignment' failed

Fix it by setting top_srcdir in the affected Makefiles.

Fixes: b2d35fa5fc80 ("selftests: add headers_install to lib.mk")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

selftests: remove duplicated all and clean target

Currently, kselftest use TEST_PROGS, TEST_PROGS_EXTENDED, TEST_FILES to
indicate the test program, extended test program and test files. It is
easy to understand the purpose of these files. But mix of compiled and
uncompiled files lead to duplicated "all" and "clean" targets.

In order to remove the duplicated targets, introduce TEST_GEN_PROGS,
TEST_GEN_PROGS_EXTENDED, TEST_GEN_FILES to indicate the compiled
objects.

Also, the later patch will make use of TEST_GEN_XXX to redirect these
files to output directory indicated by KBUILD_OUTPUT or O.

And add this changes to "Contributing new tests(details)" of
Documentation/kselftest.txt.

Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests: Add install support for the powerpc tests

The bulk of the selftests are actually below the powerpc sub directory.

This adds support for installing them, when on a powerpc machine, or if
ARCH and CROSS_COMPILE are set appropriately.

This is a little more complicated because of the sub directory structure
under powerpc, but much of the common logic in lib.mk is still used. The
net effect of the patch is still a reduction in code.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests/powerpc: Add test of load_unaligned_zero_pad()

It is a rarely exercised case, so we want to have a test to ensure it
works as required.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>