overwrite xformers in the unclip model config if not available

modules/sd_models.py

@@ -383,6 +383,9 @@ def repair_config(sd_config):
     elif shared.cmd_opts.upcast_sampling:
         sd_config.model.params.unet_config.params.use_fp16 = True
 
+    if getattr(sd_config.model.params.first_stage_config.params.ddconfig, "attn_type", None) == "vanilla-xformers" and not shared.xformers_available:
+        sd_config.model.params.first_stage_config.params.ddconfig.attn_type = "vanilla"
+
     # For UnCLIP-L, override the hardcoded karlo directory
     if hasattr(sd_config.model.params, "noise_aug_config") and hasattr(sd_config.model.params.noise_aug_config.params, "clip_stats_path"):
         karlo_path = os.path.join(paths.models_path, 'karlo')