cpufreq: interactive: remove boostpulse related code

Boostpulse is supposed to decrease GUI latency (or improve GUI response)
but it is designed in the userspace and supposed to receive the pulse
signal from user-space service via sysfs interface. It is not a good idea
to place the latency sensitive code outside kernel. Removal of this code will
theoretically increase the efficiency of interactive governor since there wil
be fewer sysfs variables to monitor. Get rid of this useless feature since
touchboost service is disabled in the user space anyway.

by mrg666