The helpers for verifiying that cpufreq and cpuidle are enabled
use let which is a bash extension and not supported in standard
POSIX shell, including with busybox. Convert to use expr which
is standard.
Signed-off-by: Mark Brown <broonie@kernel.org>
Add helper files to check if cpufreq and cpuidle are enabled. Also
add the test support for db845c.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>