[MEDIUM] checks: set server state to one state from failure when leaving maintenance

When we're enabling a server again (unix CLI or stats interface), we must not mark
it completely up because it can take a while before a failure is detected. So we
mark it one step above failure, which means it's up but will be marked down upon
first failure.
(cherry picked from commit 83c3e06452457ed5660fc814cbda5bf878bf19a2)

src/dumpstats.c

@@ -755,12 +755,14 @@ int stats_sock_parse_request(struct stream_interface *si, char *line)
 					*/
 					if (sv->tracked->state & SRV_RUNNING) {
 						set_server_up(sv);
+						sv->health = sv->rise;	/* up, but will fall down at first failure */
 					} else {
 						sv->state &= ~SRV_MAINTAIN;
 						set_server_down(sv);
 					}
 				} else {
 					set_server_up(sv);
+					sv->health = sv->rise;	/* up, but will fall down at first failure */
 				}
 			}
 

src/proto_http.c

@@ -2931,6 +2931,7 @@ int http_process_req_stat_post(struct session *s, struct buffer *req)
 						if ((sv->state & SRV_MAINTAIN)) {
 							/* Already in maintenance, we can change the server state */
 							set_server_up(sv);
+							sv->health = sv->rise;	/* up, but will fall down at first failure */
 							s->data_ctx.stats.st_code = STAT_STATUS_DONE;
 						}
 						break;