cifs: Fix lost destroy smbd connection when MR allocate failed

If the MR allocate failed, the smb direct connection info is NULL,
then smbd_destroy() will directly return, then the connection info
will be leaked.

Let's set the smb direct connection info to the server before call
smbd_destroy().

Fixes: c7398583340a ("CIFS: SMBD: Implement RDMA memory registration")
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/smbdirect.c

@@ -1700,6 +1700,7 @@ static struct smbd_connection *_smbd_get_connection(
 
 allocate_mr_failed:
 	/* At this point, need to a full transport shutdown */
+	server->smbd_conn = info;
 	smbd_destroy(server);
 	return NULL;