netbsd-queue: actually use the Config.in file

In commit e84fd04e, Yann added a
Config.in symbol for netbsd-queue in a brand new Config.in file. But
that Config.in file was never included anywhere, making it somewhat
useless.

Let's include it under Libraries -> Other, even if its actual
inclusion location doesn't matter much since it's just a hidden
Config.in option anyway.

Fixes:

  http://autobuild.buildroot.org/results/d23/d23a1c51c4d7a260364aeef576fdf5a407abc2f6/



Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>