libimxvpuapi: add new package

This is a library for using the i.MX6 VPU. It is an alternative to
libfslvpuwrap, hosted on Github, and has an API that features several
improvements over libfslvpuwrap, which include:

* User-defined context information associated with input frames, which
is passed on to corresponding output frames (to be able to identify
which input frame produced which output frame)
* Groundwork for future DMA-BUF/BMM/ION/CMA allocator integration, using
file descriptors instead of physical addresses
* Indicators for when it is safe to try to decode frames, which is
critical in multi-threaded playback cases
* Simplified, higher-level JPEG en/decoding API, based on the VPU MJPEG
codec; useful for picture viewing without the extra boilerplate for
VPU-based en/decoding

Changelog 0.10.0 -> 0.10.1:
- add debian packaging files
- update waf to version 1.8.16
- add workaround in wscript to prevent stale pkg-config .pc files
- fix memory leak by adding missing IOFreeVirtMem() call in vpulib
backend

This patch is based on the Yocto equivalent:
https://github.com/Freescale/meta-fsl-arm/commit/e519d6c
https://github.com/Freescale/meta-fsl-arm/commit/1dd6a5b

This package has been implicitely tested through gstreamer as the
plugins rely on it for vpu decoding:
 # gst-launch-1.0 playbin uri=file:///root/tears_of_steel_1080p.webm



Tested-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>