BUG/MEDIUM: servers: Don't use the same srv flag for cookie-set and TFO.

The tfo code was based on an old patch, and the value of the SRV_F_FASTOPEN
flag it used was since reused for SRV_F_COOKIESET. So give SRV_F_FASTOPEN
its own value.
diff --git a/include/types/server.h b/include/types/server.h
index 1a7109a..24e4d89 100644
--- a/include/types/server.h
+++ b/include/types/server.h
@@ -143,7 +143,7 @@
 #define SRV_F_CHECKPORT    0x0040        /* this server has a check port configured */
 #define SRV_F_AGENTADDR    0x0080        /* this server has a agent addr configured */
 #define SRV_F_COOKIESET    0x0100        /* this server has a cookie configured, so don't generate dynamic cookies */
-#define SRV_F_FASTOPEN     0x0100        /* Use TCP Fast Open to connect to server */
+#define SRV_F_FASTOPEN     0x0200        /* Use TCP Fast Open to connect to server */
 
 /* configured server options for send-proxy (server->pp_opts) */
 #define SRV_PP_V1               0x0001   /* proxy protocol version 1 */