Pull Kbuild fixes from Masahiro Yamada:
- fix cross-compilation for architectures that setup CROSS_COMPILE in
their arch Makefile
- fix Kconfig rational operators for bool / tristate
- drop a gperf-generated file from .gitignore
* tag 'kbuild-fixes-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
genksyms: drop *.hash.c from .gitignore
kconfig: fix relational operators for bool and tristate symbols
kbuild: move cc-option and cc-disable-warning after incl. arch Makefile