nv50: GP_REG_ALLOC_RESULT must be positive

Set max_out to 1 when there are no outputs.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>

src/gallium/drivers/nouveau/nv50/nv50_program.c

@@ -122,6 +122,8 @@ nv50_vertprog_assign_slots(struct nv50_ir_prog_info *info)
    }
    prog->out_nr = info->numOutputs;
    prog->max_out = n;
+   if (!prog->max_out)
+      prog->max_out = 1;
 
    if (prog->vp.psiz < info->numOutputs)
       prog->vp.psiz = prog->out[prog->vp.psiz].hw;