Revert "sched/fair: Fix value reported by hot tasks pulled in /proc/schedstat"

This reverts commit c7971fc0 which is
commit a430d99e upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I01d968c429db7eb2a0e92e888f9a8ec5780347ee
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>