cpufreq: Add Relaxed governor

Relaxed is a governor based on chill, but impliments a boost_ceiling parameter that allows for more gradual boosting. With chill, I noticed that the min and max frequencies were being used the most, and all other frequencies were being barely used at all. Rather than boosting straight to the max frequency, relaxed finds the differenced between boost_counter and boost_ceiling, then boosts to max minus that difference. For example, if boost_count is 8 and boost_ceiling is 12, when boost_counter reaches 8, the cpu freq will boost to 4 (12-8) levels below max, then increase if needed untill boost_counter reaches boost_ceiling. This governor doesn't completely replace chill, but is intended to be used alongside it. Since the lowest frequency on a57 cores uses more power than the highest freq on a53 cores, it is still valuable to use chill on a57 in order to complete a task as quickly as possible.

Change-Id: I0327de2c89475789099623232c71376cd6e375d0
Signed-off-by: Joe Maples <joe@frap129.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>