Short answer is you can't do that in Blender.
BMesh geometry engine doesn't support edge islands. Groups of edges belonging to a face must at all times be interconnected. As such "holes" or other geometry arising inside other faces can't be totally disconnected from the surrounding edges defining that face.
There must be at least one edge connecting the those buttons to the surrounding edges, unless they are made loose from the geometry.
A better question however is whether you actually want to do that or not.
Eliminating those edges will gain you nothing, neither in terms of performance nor workflow. The performance gains from one or two faces is negligible, and in any case having a huge ngon most likely yields the same final triangle count as having proper edges there anyway.
It may in fact end up being harmful, using NGons is widely regarded as an undesirable modeling practice that is bound to give problems later. You can no longer loop-cut or take advantage of edge flow or loop tools while modeling, and may encounter issues while texturing, rigging, animating, possibly yielding unexpected artifacts.
As suggested by Mr Zak you are probably better off using a proper topology with a healthy quads dominant geometry, making good use of consistent edge loops, and uniform density as seen in the linked topology guide.