Fix to device

Author: r9y9

deepvoice3_pytorch/modules.py

@@ -237,4 +237,5 @@ def get_mask_from_lengths(memory, memory_lengths):
     """
     max_len = max(memory_lengths)
     mask = torch.arange(max_len).expand(memory.size(0), max_len) < torch.tensor(memory_lengths).unsqueeze(-1)
+    mask = mask.to(memory.device)
     return ~mask