Currently the minimal up_threshold is 11, and user may want to
use a smaller minimal up_threshold for performance tuning,
so MIN_FREQUENCY_UP_THRESHOLD could be set to 1 because:

1. Current systems wouldn't be affected as they have already
   a value >= 11.
2. New systems with a default kernel would keep still the default
   value that is >= 11.

Users now have the advantage that they can make their own decisions
and customize the 'trip point' to switch to the max frequency.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=65501Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>