Return the log's reserved disk blocks also for recycle

Otherwise it looks like a rewrite would leak log blocks.

src/fellow_log.c

@@ -2041,6 +2041,8 @@ logbuffer_recycle(struct fellow_fd *ffd, struct fellow_logbuffer *lbuf,
 	CHECK_OBJ_NOTNULL(ffd, FELLOW_FD_MAGIC);
 	AN(lbuf);
 
+	logbuffer_fini_dskreqs(lbuf);
+
 	logbuffer_assert_empty(lbuf);
 	logbuffer_wait_flush_fini(lbuf);