RDMA/hw/hfi1/file_ops: Fix' manage_rcvq()'s 'arg' param

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

 drivers/infiniband/hw/hfi1/file_ops.c:1533: warning: Function parameter or member 'arg' not described in 'manage_rcvq'
 drivers/infiniband/hw/hfi1/file_ops.c:1533: warning: Excess function parameter 'start_stop' description in 'manage_rcvq'

Link: https://lore.kernel.org/r/20210121094519.2044049-26-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>

drivers/infiniband/hw/hfi1/file_ops.c

@@ -1522,7 +1522,7 @@ int hfi1_set_uevent_bits(struct hfi1_pportdata *ppd, const int evtbit)
  * manage_rcvq - manage a context's receive queue
  * @uctxt: the context
  * @subctxt: the sub-context
- * @start_stop: action to carry out
+ * @arg: start/stop action to carry out
  *
  * start_stop == 0 disables receive on the context, for use in queue
  * overflow conditions.  start_stop==1 re-enables, to be used to