network setup: calculate broadcast based on ip and netmask

Origin commit data
------------------
Commit: 336dbca45c
Author: martii <m4rtii@gmx.de>
Date: 2015-05-12 (Tue, 12 May 2015)

src/gui/network_setup.h

@@ -96,6 +96,7 @@ class CNetworkSetup : public CMenuTarget, CChangeObserver
 		bool checkForIP();
 		bool settingsChanged();
 		const char * mypinghost(std::string &host);
+		void setBroadcast(void);
 				
 	public:	
 		enum NETWORK_DHCP_MODE