staging: lustre: update comment for lnet_lib_init/exit

The documentation about the return values for lnet_lib_init
and lnet_lib_exit was in the old style format. Bring it in
sync with the rest of the LNet core. Broken out of patch 16787.
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6204
Reviewed-on: http://review.whamcloud.com/16787Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Frank Zago <fzago@cray.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lnet/lnet/api-ni.c

@@ -1389,7 +1389,8 @@ lnet_startup_lndnis(struct list_head *nilist)
  * lnet_lib_exit() after a call to lnet_lib_init(), if and only if the
  * latter returned 0. It must be called exactly once.
  *
- * \return 0 on success, and -ve on failures.
+ * \retval 0 on success
+ * \retval -ve on failures.
  */
 int lnet_lib_init(void)
 {