Currently prepare_ack_packet writes almost all the fields of the BTH in the ack packet twice. Replace code with the subroutine init_bth(). Fixes: 8700e3e7c485 ("Soft RoCE driver") Link: https://lore.kernel.org/r/20210618045742.204195-6-rpearsonhpe@gmail.com Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>