This patch replaces CLOCK_TICK_RATE with PIT_TICK_RATE, in name only. 
The use of PIT_TICK_RATE is historic with the KIOCSOUND and KDMKTONE 
ioctls; howwever, it used to be the platform-dependent CLOCK_TICK_RATE 
between kernel version 2.6.12 and 2.6.36, which was a minor but 
unfortunate ABI change that ended up polluting, at least in name, beep 
as well.