staging: lustre: Fix do not use C99 // comments in lcommon_cl.c

This patch fixed "ERROR: do not use C99 // comments" found by
checkpatch.pl in lcommon_cl.c
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/lclient/lcommon_cl.c

@@ -162,7 +162,7 @@ struct lu_context_key ccc_session_key = {
 
 
 /* type constructor/destructor: ccc_type_{init,fini,start,stop}(). */
-// LU_TYPE_INIT_FINI(ccc, &ccc_key, &ccc_session_key);
+/* LU_TYPE_INIT_FINI(ccc, &ccc_key, &ccc_session_key); */
 
 int ccc_device_init(const struct lu_env *env, struct lu_device *d,
 			   const char *name, struct lu_device *next)