Commits
Masahiro Yamada committed ab65006b08c
kconfig: use bool instead of boolean for type definition attributes
Linux stopped the use of keyword 'boolean' in Kconfig.
Refer to commit 6341e62b212a2541efb0160c470e90bd226d5496 ("kconfig:
use bool instead of boolean for type definition attributes")
in Linux Kernel.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>