scoutfs: inc end when search xattrs retries

In the rare case that searching for xattrs only finds deletions within
its window it retries the search past the window.  The end entry is
inclusive and is the last entry that can be returned.  When retrying the
search we need to start from the entry after that to ensure forward
progress.

Signed-off-by: Zach Brown <zab@versity.com>

kmod/src/srch.c

@@ -1054,6 +1054,7 @@ retry:
 	/* keep searching if we didn't find any entries in the limit */
 	if (sroot->nr == 0 && sre_cmp(&end, &final) < 0) {
 		start = end;
+		sre_inc(&start);
 		scoutfs_inc_counter(sb, srch_search_retry_empty);
 		goto retry;
 	}