tsc_khz export problem

[Wenji Huang]

Hi,

   In latest systemtap source, CONFIG_TSC_KHZ is added. But, find one 
problem about tsc_khz.
-----------------------------------------------------
               kernel              exported    declaration(tsc.h)
    i386       2.6.18 - 2.6.22         no         yes
    i386        2.6.23                yes         yes

    x86_64     2.6.22                 yes         yes
    x86_64     2.6.23                 yes         yes
------------------------------------------------------
So, for i386. in 2.6.18 - 2.6.22.  There will be an error reporting 
"Unknown symbol tsc_khz" when executing any stap script.

Regards,
wenji