net/neighbour: queue work on power efficient wq

Workqueue used in neighbour layer have no real dependency of scheduling these on
the cpu which scheduled them.

On a idle system, it is observed that an idle cpu wakes up many times just to
service this work. It would be better if we can schedule it on a cpu which the
scheduler believes to be the most appropriate one.

This patch replaces normal workqueues with power efficient versions. This
doesn't change existing behavior of code unless CONFIG_WQ_POWER_EFFICIENT is
enabled.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
fastcharge: New enhancements

* Add 1800 mA level
* Add "fake_charge_ac" hack. If fast charge is on with fake_charge_ac = 1,
  device will show current source as AC instead of USB.
* By default, fake_charge_ac is disabled.

Sincere thanks to mankindtw@xda for idea.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
fs: exfat: Update to v1.2.8
untracked file