IB/core: Remove unimplemented ib_peek_cq

ib_peek_cq() verb doesn't seem be implemented in current code.
There is some past reference to it at [1] about it being unimplemented.

Lot of user documentation created out of kdoc refers to this
unimplemented API. Therefore, remove unimplemented API.

[1] http://lists.openfabrics.org/pipermail/ofw/2008-May/002465.html
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

include/rdma/ib_verbs.h

@@ -3225,18 +3225,6 @@ static inline int ib_poll_cq(struct ib_cq *cq, int num_entries,
 	return cq->device->poll_cq(cq, num_entries, wc);
 }
 
-/**
- * ib_peek_cq - Returns the number of unreaped completions currently
- *   on the specified CQ.
- * @cq: The CQ to peek.
- * @wc_cnt: A minimum number of unreaped completions to check for.
- *
- * If the number of unreaped completions is greater than or equal to wc_cnt,
- * this function returns wc_cnt, otherwise, it returns the actual number of
- * unreaped completions.
- */
-int ib_peek_cq(struct ib_cq *cq, int wc_cnt);
-
 /**
  * ib_req_notify_cq - Request completion notification on a CQ.
  * @cq: The CQ to generate an event for.