panvk: quiet non-conformant warning on ci

This helper has built-in support to be quieted, which seems like a good
idea to do on ci.

We're already setting the env var in the CI environment, so no need to
do that here.

Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16033>

src/panfrost/vulkan/panvk_device.c

@@ -342,8 +342,7 @@ panvk_physical_device_init(struct panvk_physical_device *device,
       goto fail_close_device;
    }
 
-   fprintf(stderr, "WARNING: panvk is not a conformant vulkan implementation, "
-                   "testing use only.\n");
+   vk_warn_non_conformant_implementation("panvk");
 
    panvk_get_driver_uuid(&device->device_uuid);
    panvk_get_device_uuid(&device->device_uuid);