Fixes the following W=1 kernel build warning(s):

 drivers/cpufreq/intel_pstate.c:293: warning: Function parameter or member 'get_aperf_mperf_shift' not described in 'pstate_funcs'
Suggested-by: N"Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
[ rjw: Remove line break ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>