[Minor] Remove sequential algorithm as it is not actually a rotation alg

Sequential rotation was used just to rotate all upstreams in the loop (e.g.
when you need to do some action for all upstreams). Allowing to specify it as
a user defined algorithm was a mistake as it breaks upstreams API expectations.
See #4043

diff --git a/src/libutil/upstream.c b/src/libutil/upstream.c
index 578efd0f480b50f471c85f6db21427bfa12bebf1..835785acbe64790624887043e907c602bf39f251 100644 (file)
--- a/src/libutil/upstream.c
+++ b/src/libutil/upstream.c
@@ -1241,10 +1241,6 @@ rspamd_upstreams_parse_line_len (struct upstream_list *ups,
                ups->rot_alg = RSPAMD_UPSTREAM_HASHED;
                p += sizeof ("hash:") - 1;
        }
-       else if (RSPAMD_LEN_CHECK_STARTS_WITH(p, len, "sequential:")) {
-               ups->rot_alg = RSPAMD_UPSTREAM_SEQUENTIAL;
-               p += sizeof ("sequential:") - 1;
-       }
 
        while (p < end) {
                span_len = rspamd_memcspn (p, separators, end - p);