tools/power turbostat: fix IVB support

Initial IVB support went into turbostat in Linux-3.1:
553575f1


(tools turbostat: recognize and run properly on IVB)

However, when running on IVB, turbostat would fail
to report the new couters added with SNB, c7, pc2 and pc7.
So in scenarios where these counters are non-zero on IVB,
turbostat would report erroneous residencey results.

In particular c7 time would be added to c1 time,
since c1 time is calculated as "that which is left over".

Also, turbostat reports MHz capabilities when passed
the "-v" option, and it would incorrectly report 133MHz
bclk instead of 100MHz bclk for IVB, which would inflate
GHz reported with that option.

This patch is a backport of a fix already included in turbostat v2.

Signed-off-by: Len Brown <len.brown@intel.com>