staging: lustre: obdecho: constify lu_device_operations and cl_device_operations structures

These lu_device_operations and cl_device_operations structures are never
modified, so declare them as const.  Other structures of these types are
already const.

Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/obdecho/echo_client.c

@@ -582,13 +582,13 @@ static struct lu_object *echo_object_alloc(const struct lu_env *env,
 	return obj;
 }
 
-static struct lu_device_operations echo_device_lu_ops = {
+static const struct lu_device_operations echo_device_lu_ops = {
 	.ldo_object_alloc   = echo_object_alloc,
 };
 
 /** @} echo_lu_dev_ops */
 
-static struct cl_device_operations echo_device_cl_ops = {
+static const struct cl_device_operations echo_device_cl_ops = {
 };
 
 /** \defgroup echo_init Setup and teardown