CryptoPP compilation fixes for gcc 4.7

( http://forum.mc-server.org/showthread.php?tid=520&pid=4829#pid4829 )

git-svn-id: http://mc-server.googlecode.com/svn/trunk@941 0a769ca7-a7f5-676a-18bf-c427514a06d6

CryptoPP/hrtimer.cpp

@@ -70,7 +70,6 @@ TimerWord Timer::GetCurrentTimerValue()
 	gettimeofday(&now, NULL);
 	return (TimerWord)now.tv_sec * 1000000 + now.tv_usec;
 #else
-	clock_t now;
 	return clock();
 #endif
 }