The CPUIDLE_DRIVER_STATE_START constant is only set when the kernel compilation
option CONFIG_ARCH_HAS_CPU_RELAX is set, but this is only relatated to x86, so
it is always zero.

Remove the reference to this constant in the code.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>