ceph: include auth method in error messages

Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/auth.h b/fs/ceph/auth.h
index ca4f57c..4429a70 100644
--- a/fs/ceph/auth.h
+++ b/fs/ceph/auth.h
@@ -15,6 +15,8 @@
 struct ceph_authorizer;
 
 struct ceph_auth_client_ops {
+	const char *name;
+
 	/*
 	 * true if we are authenticated and can connect to
 	 * services.