RDMA/ucma: Avoid sending reject if backlog is full

Change the returned error code to ENOMEM if the connection event
backlog is full.  This prevents the ib_cm from issuing a reject
on the connection, which can allow retries to succeed.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index b516b93..c859134 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -266,7 +266,7 @@
 	mutex_lock(&ctx->file->mut);
 	if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST) {
 		if (!ctx->backlog) {
-			ret = -EDQUOT;
+			ret = -ENOMEM;
 			kfree(uevent);
 			goto out;
 		}