cpufreq: cpu-boost: Don't register for cpufreq notifiers too early

The cpufreq notifiers should be registered only after all the data
structures used in the notifier callbacks have been initialized. So, move
the cpufreq notifier registration to a later point in the init function.

Change-Id: I043ab5bc0ebb98164c40549fe151a8d801c8c186
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
cpuboost: Add hotplug boosting

If we decide to hotplug a core then we are making a strong
statement that we think that the system load is high.  Let's
have faith in our hotplug driver(s) and boost the cpufreq
when we are hotplugging cores.

[myfluxi: shorter boost, minor style changes]

[temasek: plug_boost_freq 1190400]

Change-Id: Id35bae6c27c39097c7aca70eebf1498ed0c3dfdc
msm: rq_stats: Disable hotplug and stats by default

Userspace closed source mpdecision binary is nessecary for PowerHAL to work.
As it depends on rq_stats, let's at least disable hotplugging and stats
collection by default. /sys/devices/system/cpu/cpu0/rq-stats/hotplug_disable
is now writable, so hotplug can be reenabled.

Also, add some bits related to current cpu policy.