CLEANUP: stick-table: no need to include socket nor in.h

The types provided by these are never present in stick_table-t.h,
let's drop them.
diff --git a/include/haproxy/stick_table-t.h b/include/haproxy/stick_table-t.h
index 9dd4ede..f1f9d23 100644
--- a/include/haproxy/stick_table-t.h
+++ b/include/haproxy/stick_table-t.h
@@ -23,9 +23,6 @@
 #ifndef _HAPROXY_STICK_TABLE_T_H
 #define _HAPROXY_STICK_TABLE_T_H
 
-#include <sys/socket.h>
-#include <netinet/in.h>
-
 #include <import/eb32tree.h>
 #include <import/ebmbtree.h>
 #include <import/ebpttree.h>