cpufreq: Add module to register cpufreq on Krait CPUs

Register a cpufreq-generic device whenever we detect that a
"qcom,krait" compatible CPU is present in DT.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[Sricharan: updated to use dev_pm_opp_set_prop_name and
	    nvmem apis]
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
[Thierry Escande: update to add support for opp-supported-hw]
Signed-off-by: Thierry Escande <thierry.escande@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>