Improvements to T.4 end of image handling, and the related tests.

A lot of tiny tidy up edits

libs/spandsp/src/bert.c

@@ -491,7 +491,7 @@ SPAN_DECLARE(bert_state_t *) bert_init(bert_state_t *s, int limit, int pattern,
     span_log_init(&s->logging, SPAN_LOG_NONE, NULL);
     span_log_set_protocol(&s->logging, "BERT");
 
-    return  s;
+    return s;
 }
 /*- End of function --------------------------------------------------------*/