gpio: Introduce CONFIG_GPIO_EXTRA_HEADER to cleanup #ifdefs

Since some SoCs and boards do not hae extra asm/arch/gpio.h,
introduce CONFIG_GPIO_EXTRA_HEADER instead of adding
!define(CONFIG_ARCH_XXXX) in asm/gpio.h.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu@linaro.org>
2 files changed