Fix off-by-one bug in range tree code

Without this fix, zfs_range_tree_find_in could return an overlap when
the found range starts immediately after the searched range, with no
actual overlap.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Alexander Motin <[email protected]>
Reviewed by: Igor Kozhukhov <[email protected]>
Signed-off-by: Paul Dagnelie <[email protected]>
Closes #17363

Author: pcd1193182

module/zfs/range_tree.c

@@ -659,7 +659,7 @@ zfs_range_tree_find_in(zfs_range_tree_t *rt, uint64_t start, uint64_t size,
 	}
 
 	rs = zfs_btree_next(&rt->rt_root, &where, &where);
-	if (rs == NULL || zfs_rs_get_start(rs, rt) > start + size)
+	if (rs == NULL || zfs_rs_get_start(rs, rt) >= start + size)
 		return (B_FALSE);
 
 	*ostart = zfs_rs_get_start(rs, rt);