Fix SteamNetworkingUtils() interface for SteamAPI dedicated server

The way we fallback to gameserver or user doesn't work anymore.
SteamInternal_FindOrCreateUserInterface now crashes if called
before steam is initted.

P4:10716251
(cherry picked from commit f1edd32d2a6d71cfc0568112610752a28666f585)

Author: zpostfacto

include/steam/isteamnetworkingutils.h

@@ -10,6 +10,7 @@
 
 #include "steamnetworkingtypes.h"
 #include "steam_api_common.h"
+#include "isteamclient.h"
 
 struct SteamDatagramRelayAuthTicket;
 struct SteamRelayNetworkStatus_t;
@@ -368,13 +369,9 @@ class ISteamNetworkingUtils
 #endif
 
 // Using Steamworks SDK
-#ifdef STEAMNETWORKINGSOCKETS_STEAMAPI
+#if defined( STEAMNETWORKINGSOCKETS_STEAMAPI )
 	STEAM_DEFINE_INTERFACE_ACCESSOR( ISteamNetworkingUtils *, SteamNetworkingUtils_SteamAPI,
-		/* Prefer user version of the interface.  But if it isn't found, then use
-		gameserver one.  Yes, this is a completely terrible hack */
-		SteamInternal_FindOrCreateUserInterface( 0, STEAMNETWORKINGUTILS_INTERFACE_VERSION ) ?
-		SteamInternal_FindOrCreateUserInterface( 0, STEAMNETWORKINGUTILS_INTERFACE_VERSION ) :
-		SteamInternal_FindOrCreateGameServerInterface( 0, STEAMNETWORKINGUTILS_INTERFACE_VERSION ),
+		( (ISteamClient *)SteamInternal_CreateInterface( STEAMCLIENT_INTERFACE_VERSION ) )->GetISteamGenericInterface( 0, SteamAPI_GetHSteamPipe() ? SteamAPI_GetHSteamPipe() : SteamGameServer_GetHSteamPipe(), STEAMNETWORKINGUTILS_INTERFACE_VERSION ),
 		"global",
 		STEAMNETWORKINGUTILS_INTERFACE_VERSION
 	)