The AIROHA_CPU_PM_DOMAIN option was added inside the MediaTek PM Domains
menu, which depends on ARCH_MEDIATEK || COMPILE_TEST. Since Airoha
platforms use ARCH_AIROHA, the menu is invisible during kernel
configuration, silently dropping AIROHA_CPU_PM_DOMAIN. This breaks
running `make kernel_menuconfig`.
Add ARCH_AIROHA to the menu dependency so that this option and its
dependencies (PM_GENERIC_DOMAINS, PM_GENERIC_DOMAINS_OF) remain
enabled on Airoha targets.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>