For torch.distributed.launch ARG --local_rank should be --local-rank

[hassanbabaie]

When using -m torch.distributed.launch --nproc_per_node=2 as an example it uses --local-rank and not the expected --local_rank which generate a fatal error.

ViT-pytorch/train.py

Line 281 in 460a162

parser.add_argument("--local_rank", type=int, default=-1,

Setting the arg to local-rank in train.py resolved the issue and it then works as expected