include the unx part for getting OpenGL driver & device information

desktop/unx/source/glxtest.cxx is taken directly from the Mozilla
project.

THe whole concept is taken from Mozilla and is based on starting an
early process that creates an OpenGL context. This prevents crashing
drivers to crash Libreoffice.

We read the information from the pipe as soon as we create the first vcl
Window. In that place we then decide if the device/driver combination is
blacklisted.

Change-Id: I2624d4ce06d503281a4459cf3174f57cf1f7b733