[CPUFREQ] Longhaul - Add VT8235 support

I don't know why it is working and how, but it is working. On my
Epia transition time is by default set to 100us. I'm changing it to
200us. After that I can change frequency from min (x4.0) to max (x7.5)
without lockup. Many times.
There is a paranoid check at a beginning of a patch. Probably dead
code, but I don't have better ideas for CL10000 case at the moment.
Only way to to detect broken chip seems to be looking in log for
spurious interrupts.

Signed-off-by: Rafal Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>