examples/nvme/perf: set io_queue_size in NVMe probe

Since we know the queue depth that we will be using during the test,
request that as the queue size when attaching to NVMe controllers.

Reserve one extra queue entry above the expected queue depth since NVMe
queues must always have one entry free to distinguish between queue
empty and queue full cases.

Change-Id: I809982207edb4894148aec09b10c4e2de4a040d3
Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>

examples/nvme/perf/perf.c

@@ -1064,6 +1064,8 @@ probe_cb(void *cb_ctx, const struct spdk_nvme_transport_id *trid,
 		       pci_id.vendor_id, pci_id.device_id);
 	}
 
+	opts->io_queue_size = g_queue_depth + 1;
+
 	return true;
 }