qt5: remove Qt Quick dependency on opengl

qt5: remove Qt Quick dependency on opengl

Qt Quick should no longer depend on opengl, and instead fallback to
the limited functionality software renderer as a replacement [1] when
not available.

[1] http://blog.qt.io/blog/2016/08/15/the-qt-quick-graphics-stack-in-qt-5-8/

Cc: Peter Seiderer <ps.report@gmx.net>
Cc: Julien Corjon <corjon.j@ecagroup.com>
Signed-off-by: Joshua Henderson <joshua.henderson@microchip.com>
Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Tested-by: Peter Seiderer <ps.report@gmx.net>
[Thomas: drop qt5declarative patch, since we have bumped to 5.9.3,
which contains the patch.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>