cpufreq: Unified governor/scaling switching (squashed commits)

cpufreq: unified governor and scaling min and max switching governor scaling_min_freq and scaling_max_freq will be populated to all online cpus immediately

cpufreq: unified governor and scaling min and max switching use related_cpus to apply correctly to new online cpus

cpufreq: block hotplugging during multi-cpu operations

cpufreq: dont apply multi-cpu values if not changed

Change-Id: I199d47409d1ed15bbf9e4856d528344560c6f092