i965: Fix the passthrough TCS for isolines.

i965: Fix the passthrough TCS for isolines.

We weren't setting up several of the uniform values for the patch
header, so we'd crash when uploading push constants.  We at least
need to initialize them to zero.  We also had the isoline parameters
reversed, so it would also render incorrectly (if it didn't crash).

Fixes a new Piglit test(*) (isoline-no-tcs), as well as crashes in
GL44-CTS.tessellation_shader.single.max_patch_vertices.

(*) https://lists.freedesktop.org/archives/piglit/2016-May/019866.html

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Cc: mesa-stable@lists.freedesktop.org