sched: add SCHED_QHMP config option

QHMP scheduler provides extensions like small task classification for
task packing, load/freq/tasks based packing knobs and energy aware
task placements and load balancing. The scheduler files are duplicated
to support both QHMP and zone schedulers. Add SCHED_QHMP config
to select the QHMP scheduler at compile time.

This patch also brings the qhmp_core.c and qhmp_fair.c up-to-date with
the original files.

Change-Id: I14f96b349da784fd5cbdb26f08f6d12de9cc64d9
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>