Fix black images on some flux models in fp16. (comfyanonymous#8495)

Author: comfyanonymous

comfy/ldm/flux/model.py

@@ -187,6 +187,9 @@ def block_wrap(args):
                     if add is not None:
                         img[:, txt.shape[1] :, ...] += add
 
+        if img.dtype == torch.float16:
+            img = torch.nan_to_num(img, nan=0.0, posinf=65504, neginf=-65504)
+
         img = img[:, txt.shape[1] :, ...]
 
         img = self.final_layer(img, vec)  # (N, T, patch_size ** 2 * out_channels)