i965: Account for TES in is_drawing_points().
i965: Account for TES in is_drawing_points().

Now that we implement tessellation shaders, the TES might be the last
stage enabled.  If it's outputting points, then the primitive type
reaching the SF is points.  We need to account for this.

Caught by Ilia Mirkin.

v2: Update dirty bit comment above caller (caught by Iago)

Signed-off-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>
Reviewed-by: Iago Toral Quiroga <a847aabaac44184372f6b1cd1a59aa254daaeb0b@igalia.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler