cpufreq: hotplug: patch hotplug governor to use workqueues when enabling/disabling the second core

credits
 - siyah
cpufreq: hotplug: make hotplug plug in/out more than one core depending on the load

credits:
 siyah
cpufreq: pegasusq: some pegasusq tweaks (credit siyah)

- increase up_threshold_at_min_freq
- make freq_for_responsiveness and up_threshold_at_min_freq configurable
- make hotplug_history circular
- make it a little harder to enable cores
cpufreq: pegasusq: remove unused cpu up/down freq (credit: siyah)