Fixes the following W=1 kernel build warning(s):

 drivers/infiniband/hw/hfi1/exp_rcv.c:56: warning: Function parameter or member 'set' not described in 'hfi1_exp_tid_set_init'
 drivers/infiniband/hw/hfi1/exp_rcv.c:66: warning: Function parameter or member 'rcd' not described in 'hfi1_exp_tid_group_init'
 drivers/infiniband/hw/hfi1/exp_rcv.c:77: warning: Function parameter or member 'rcd' not described in 'hfi1_alloc_ctxt_rcv_groups'
 drivers/infiniband/hw/hfi1/exp_rcv.c:114: warning: Function parameter or member 'rcd' not described in 'hfi1_free_ctxt_rcv_groups'

Link: https://lore.kernel.org/r/20210121094519.2044049-24-lee.jones@linaro.org
Cc: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>