Some cpufreq drivers implement their own governor and so don't need
us to call generic governors interface via __cpufreq_governor(). Few
recent commits haven't obeyed this law well and we saw some
regressions.

This patch is an attempt to fix the above issue.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Reported-and-tested-by: NSedat Dilek <sedat.dilek@gmail.com>
Tested-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>