codel: backport from v3.5 kernel.

codel: backport from v3.5 kernel.

Controlled Delay queue management algorithm.

See: http://lwn.net/Articles/496509/

Contains the baseline addition of the support, plus the
subsequent tweaks and error fixes.  Imports of mainline
commits as follows:

codel-Controlled-Delay-AQM.patch:
	76e3cc126bb223013a6b9a0e2a51238d1ef2e409
codel-refine-one-condition-to-avoid-a-nul-rec_inv_sq.patch:
	2359a47671fc4fb0fe5e9945f76c2cb10792c0f8
codel-use-Newton-method-instead-of-sqrt-and-divides.patch:
	536edd67109df5e0cdb2c4ee759e9bade7976367
codel-use-u16-field-instead-of-31bits-for-rec_inv_sq.patch:
	6ff272c9ad65eda219cd975b9da2dbc31cc812ee
fq_codel-Fair-Queue-Codel-AQM.patch:
	4b549a2ef4bef9965d97cbd992ba67930cd3e0fe
fq_codel-should-use-qdisc-backlog-as-threshold.patch:
	865ec5523dadbedefbc5710a68969f686a28d928
net-codel-Add-missing-include-linux-prefetch.h.patch:
	ce5b4b977127ee20c3f9c3fd3637cd3796f649f5
net-codel-fix-build-errors.patch:
	669d67bf777def468970f2dcba1537edf3b2d329
netem-add-ECN-capability.patch:
	e4ae004b84b315dd4b762e474f97403eac70f76a

This exact list has been in use in the Yocto 3.4 kernel for
several months now.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>