tools/power turbostat: decode BXT TSC frequency via CPUID

tools/power turbostat: decode BXT TSC frequency via CPUID

BugLink: http://bugs.launchpad.net/bugs/1591802
Hard-code BXT ART to 19200MHz, so turbostat --debug
can fully enumerate TSC:

CPUID(0x15): eax_crystal: 3 ebx_tsc: 186 ecx_crystal_hz: 0
TSC: 1190 MHz (19200000 Hz * 186 / 3 / 1000000)

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit e8efbc80db5e824ce2382d5e65429b6b493e71e2)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>
Acked-by: Kamal Mostafa <kamal@canonical.com>