cpufreq: Send START policy notification after sending CREATE

The sequence got a bit wrong as we are sending CPUFREQ_START
notifications even before we have sent CPUFREQ_CREATE_POLICY.

Fix it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>