Squash BFQ commits

Add bfq io scheduler

Conflicts:
	include/linux/cgroup_subsys.h

Conflicts:
	block/Makefile

block: Switch from BFQ-v7r2 for 3.4.0 to BFQ-v7r3 for 3.4.0

. IMPROVEMENT: Improved throughput boosting with NCQ-capable HDDs and
  random workloads. The mechanism that further boosts throghput with
  these devices and workloads is activated only in the cases where it
  does not cause any violation of throughput-distribution and latency
  guarantees.
. IMPROVEMENT: Generalized the computation of the parameters of the
  low-latency heuristic for interactive applications, so as to fit also
  slower storage devices. The purpose of this improvement is to preserve
  low-latency guarantees for interactive applications also on slower
  devices, such as portable hard disks, multimedia and SD cards.
. BUGFIX: Re-added MODULE_LICENSE macro.
. CODE IMPROVEMENTS: Small code cleanups; introduced a coherent naming
  scheme for all identifiers related to weight raising; refactored and
  optimized a few hot paths.

Signed-off-by: Paolo Valente <paolo.valente@unimore.it>
Signed-off-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
Reported-by: Mikhail Akushsky <namelles.one@gmail.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>

Update BFQ to v7r4

Budget Fair Queueing I/O Scheduler
==================================

This patchset introduces BFQ-v7r4 into Linux 3.4.0.
For further information: http://www.algogroup.unimo.it/people/paolo/disk_sched/.

CHANGELOG

v7r4:
. BUGFIX. Modified the code so as to be robust against late detection of
  NCQ support for a rotational device.
. BUGFIX. Removed a bug that hindered the correct throughput distribution
  on flash-based devices when not every process had to receive the same
  fraction of the throughput. This fix entailed also a little efficiency
  improvement, because it implied the removal of a short function executed
  in a hot path.
. CODESTYLE IMPROVEMENT: removed quoted strings split across lines.

Change-Id: I2bb2abc14204c72a2c9e1e4037b57126c03a64d0
CREDIT: Paolo Valente