cpufreq: cpu-boost: Implement additional checks

* Return early without calculations if last
  input_boost_work is pending.
* Disable input boost if input_boost_freq value is
  less than or equal to min possible frequency.
* Disable hotplug boost if plug_boost_freq value is
  less than or equal to min possible frequency.
* When we check for current frequency greater than
  boost frequency, also check if boost is removed
  properly or not. If not, do so.

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