On ARM64 kernels between 4.4 and 4.7 inclusive, enabling ACPI_PROCESSOR
doesn't select ACPI_PROCESSOR_IDLE. This can cause link-time errors at
this line in __acpi_processor_start():
if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
Fix this by moving the comparison inside a helper, which can be
hard-coded to return 0 on kernels where ACPI_PROCESSOR_IDLE=n.
Change-Id: If3ea50021616516c513f0da8a13b2e2edbca759a
Signed-off-by: Greg Hackmann <ghackmann@google.com>
b7358cf03f