RDMA/ucma: Cleanup to reduce duplicate code

The lable "err1" does the same thing as the branch of copy_to_user()
failed in the function ucma_create_id(). Just jump to the label directly
to reduce duplicate code.

Link: https://lore.kernel.org/r/1620291106-3675-1-git-send-email-tanxiaofei@huawei.com


Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>