Revert "cpufreq: fix jiffies/cputime mixup in conservative/ondemand governors"

This reverts commit 7ae6fb41a934a2cdd8f66fd45644632001170425.
Revert "cpufreq: Move common part from governors to separate file, v2"

This reverts commit fa803c105ef491867b03c072a44dc35644614609.