Revert "overall_stats: forward port to kernel 3.4+ , thanks to @faux123"

This reverts commit 248c38e3730403eb121b0dbde140058039a392e7.
Revert "overall_stats: add overall stats for all available cores ,  thanks to @faux123"

This reverts commit 91f8062dfba58f048c73d6eb8512b3d9b7882545.