nvk: Don't print the NVK_I_WANT_A_BROKEN_VULKAN_DRIVER warning in release builds

The environment variable is still there and it still works but this
means that release builds will simply silently fail to enumerate rather
than throwing confusing warnings at users.

Reviewed-by: Joshua Ashton <joshua@froggi.es>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27832>

src/nouveau/vulkan/nvk_physical_device.c

@@ -1048,11 +1048,15 @@ nvk_create_drm_physical_device(struct vk_instance *_instance,
 
    if (!conformant &&
        !debug_get_bool_option("NVK_I_WANT_A_BROKEN_VULKAN_DRIVER", false)) {
+#ifdef NDEBUG
+      result = VK_ERROR_INCOMPATIBLE_DRIVER;
+#else
       result = vk_errorf(instance, VK_ERROR_INCOMPATIBLE_DRIVER,
                          "WARNING: NVK is not well-tested on %s, pass "
                          "NVK_I_WANT_A_BROKEN_VULKAN_DRIVER=1 "
                          "if you know what you're doing.",
                          info.device_name);
+#endif
       goto fail_ws_dev;
    }