BUG/MEDIUM: log: check result details truncated.

Fix regression introduced by commit:
'MAJOR: servers: propagate server status changes asynchronously.'

The building of the log line was re-worked to be done at the
postponed point without lack of data.

[wt: this only affects 1.8-dev, no backport needed]
diff --git a/include/types/server.h b/include/types/server.h
index 75054a0..cdc3359 100644
--- a/include/types/server.h
+++ b/include/types/server.h
@@ -300,7 +300,11 @@
 	} tmpl_info;
 	struct dns_srvrq *srvrq;		/* Pointer representing the DNS SRV requeest, if any */
 	struct list update_status;		/* to attach to list of servers chnaging status */
-	char op_st_chg_reason[48];		/* operational status change's reason */
+	struct {
+		char reason[128];
+		short status, code;
+		long duration;
+	} op_st_chg;				/* operational status change's reason */
 	char adm_st_chg_cause[48];		/* adminstrative status change's cause */
 };