staging: lustre: check length of char array

This fixes the following sparse error:

drivers/staging/lustre/lustre/obdclass/llog_ioctl.c:388:39: error: incompatible types for operation (>)
drivers/staging/lustre/lustre/obdclass/llog_ioctl.c:388:39:    left side has type char *ioc_inlbuf2
drivers/staging/lustre/lustre/obdclass/llog_ioctl.c:388:39:    right side has type int
Signed-off-by: NAndreas Platschek <platschek@ict.tuwien.ac.at>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/obdclass/llog_ioctl.c

@@ -385,7 +385,7 @@ int llog_ioctl(const struct lu_env *env, struct llog_ctxt *ctxt, int cmd,
 			GOTO(out_close, rc = -EINVAL);
 		}
 
-		if (data->ioc_inlbuf2 > 0) {
+		if (data->ioc_inllen2 > 0) {
 			/* remove indicate log from the catalog */
 			rc = str2logid(&plain, data->ioc_inlbuf2,
 				       data->ioc_inllen2);