nir/lower_viewport_transform: Allow geom/tess
This pass needs to run on the last shader in a pipeline writing gl_Position. In GLES2, that's always the vertex shader, but in ES3.2, it can be a geometry or tessellation shader. The shared code works the same in this case, just make the assert more generous.
Signed-off-by: Alyssa Rosenzweig alyssa@collabora.com