Pull Kbuild updates from Masahiro Yamada:
- Use Make-builtin $(abspath ...) helper to get absolute path
- Add W=2 extra warning option to detect unused macros
- Use more KCONFIG_CONFIG instead hard-coded .config
- Fix bugs of tar*-pkg targets
* tag 'kbuild-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: buildtar: do not print successful message if tar returns error
kbuild: buildtar: fix tar error when CONFIG_MODULES is disabled
kbuild: Use KCONFIG_CONFIG in buildtar
Kbuild: enable -Wunused-macros warning for "make W=2"
kbuild: use $(abspath ...) instead of $(shell cd ... && /bin/pwd)