msm: alucard_hotplug: Remove it

* We are not using this hotplug driver since long time.
* Clean it up.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: msm_rq_stats: Tone down mpdecision

Add a new Kconfig to enable more conservative computations sent
to mpdecision:

 * Do not make IO busy
 * Do a time window weighted load computation instead of just a sum
 * Do an sliding window averaged time computation for number runnable

The purpose of these changes is to make mpdecision less likely to
keep extra cores online.  It currently has a tendancy to run more
cores running than needed and this can even cause some lag issues.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sched: Compute avg_nr_running for RQ Stats

* We already compute avg_nr_running for intelli hotplug.
* Let's make it available for conservative stats of MSM RQ as
  well.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: msm_rq_stats: Add proper attribute to enable hotplug

* hotplug_disable attribute resets when device suspend and
  sets when device resumes.
* Thereby, the value is dynamic. Perhaps, this value is read
  by userspace, so we don't want to mess with it further.
* Restore hotplug_disable to original format of read-only.
* Introduce hotplug_enable attribute which will do the job.
* We have "enable" attribute for other hotplug drivers, so
  this implementation aligns with them.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>