Revert "PM: devfreq: Add sysfs nodes for devfreq governors"

This reverts commit 29f7443438c597adc8f809ee13c40fee0ca29208.
Revert "PM: devfreq: Always reflect a change of polling interval"

This reverts commit ac8fd06ea8d2ba8a185ece5092ce520eff072283.
Revert "PM: devfreq: Fix show available freqs"

This reverts commit 4d0bc4a5d9d1926e17aba10cf6d6e2215ae5a555.