Revert "sched/fair: Fix fairness issue on migration"

Mike reported that this recent commit:

  3a47d5124a95 ("sched/fair: Fix fairness issue on migration")

... broke interactivity and the signal starvation test.

We have a proper fix series in the works but ran out of time for
v4.6, so revert the commit.

Change-Id: I2829ed178ea73c4aff919ae76f9883e14cc1fca8
Reported-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Git-commit: 53d3bc773eaa7ab1cf63585e76af7ee869d5e709
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


[pkondeti@codeaurora.org: Resolved minor merge conflicts]
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>