[dpdk-dev] removal of unused DPDK example apps

[Bruce Richardson <bruce.richardson@intel.com>]

A standard item on the agenda of the DPDK technical board meetings has been
the number of example apps in DPDK and whether any of them can be removed.
The board would therefore like to propose that we deprecate a number of
examples in 19.08 and remove them in 19.11.

Here is my initial list of suggested apps to remove, and for a couple of
them the reasons why I consider them for removal.

* exception_path - basically a tun/tap example app, given we have KNI, and
  a tap PMD, this app is probably unneeded.
* l3fwd-vf 
* load_balancer - functionality covered by distributor and eventdev now
* multiprocess/simple_mp - NOTE: not all multi-process apps, just the
  basic, toy one!
* netmap_compat
* quota-watermark
* rxtx_callbacks
* vmdq
* vmdq_dcb

NOTE: Whatever apps are removed will still be available for people to
reference in older releases of DPDK - including our LTS's - as well as in
the git repository, they just won't be available in the latest versions,
and there will no longer be any guarantees that they will compile as DPDK
changes.  The benefits from removing any unwanted apps are that we have
less code to maintain and test, and we have smaller DPDK packages and
faster build times.

At this stage, the technical board is seeking feedback on the proposed
removal of these applications, or if there are other examples that people
feel do not add any value to DPDK and can be removed. All comments welcome.

Regards,
/Bruce