Hotfix for the div zero occurrence when memory_used_encode is 0 (Comfy-Org#5121)

Comfy-Org#5069 (comment)

Author: ltdrdata

comfy/sd.py

@@ -347,7 +347,7 @@ def encode(self, pixel_samples):
             memory_used = self.memory_used_encode(pixel_samples.shape, self.vae_dtype)
             model_management.load_models_gpu([self.patcher], memory_required=memory_used)
             free_memory = model_management.get_free_memory(self.device)
-            batch_number = int(free_memory / memory_used)
+            batch_number = int(free_memory / max(1, memory_used))
             batch_number = max(1, batch_number)
             samples = torch.empty((pixel_samples.shape[0], self.latent_channels) + tuple(map(lambda a: a // self.downscale_ratio, pixel_samples.shape[2:])), device=self.output_device)
             for x in range(0, pixel_samples.shape[0], batch_number):