ilo: winsys may limit the batch buffer size

The maximum batch buffer size is determined at the time of
drm_intel_bufmgr_gem_init().  Make sure the pipe driver does not exceed the
limit.

src/gallium/drivers/ilo/ilo_screen.c

@@ -648,6 +648,7 @@ static bool
 init_dev(struct ilo_dev_info *dev, const struct intel_winsys_info *info)
 {
    dev->devid = info->devid;
+   dev->max_batch_size = info->max_batch_size;
    dev->has_llc = info->has_llc;
    dev->has_gen7_sol_reset = info->has_gen7_sol_reset;
    dev->has_address_swizzling = info->has_address_swizzling;