util: Don't directly include config_parser.hpp

Change-Id: I6a228697d0b6d1767bf6f10b3f375e78cd8a623d
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/util.hpp b/src/util.hpp
index ded3d27..8ca8b4b 100644
--- a/src/util.hpp
+++ b/src/util.hpp
@@ -1,5 +1,4 @@
 #pragma once
-#include "config_parser.hpp"
 #include "types.hpp"
 
 #include <netinet/ether.h>
@@ -20,6 +19,10 @@
 {
 namespace network
 {
+namespace config
+{
+class Parser;
+}
 
 using EthernetInterfaceIntf =
     sdbusplus::xyz::openbmc_project::Network::server::EthernetInterface;