nv50,nvc0: implement half_pixel_center

LAST_LINE_PIXEL has actually been renamed to PIXEL_CENTER_INTEGER in
rnndb; use that method to implement the rasterizer setting, used for
st/nine.

Signed-off-by: Tiziano Bacocco <tizbac2@gmail.com>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: "10.4" <mesa-stable@lists.freedesktop.org>
gm107/ir: don't generate texbars

Latest blob drivers don't appear to, perhaps they were unncessary there.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: "10.3" <mesa-stable@lists.freedesktop.org>
wip handle scissors/color/stencil masks in clear