tools/power turbostat: decode HWP registers

tools/power turbostat: decode HWP registers

BugLink: http://bugs.launchpad.net/bugs/1591802
 # turbostat --debug
...
CPUID(6): ... HWP, HWPnotify, HWPwindow, HWPepp, HWPpkg ...
...
cpu0: MSR_PM_ENABLE: 0x00000001 (HWP)
cpu0: MSR_HWP_CAPABILITIES: 0x01050916 (high 0x16 guar 0x9 eff 0x5 low 0x1)
cpu0: MSR_HWP_REQUEST: 0x80001604 (min 0x4 max 0x16 des 0x0 epp 0x80 window 0x0 pkg 0x0)
cpu0: MSR_HWP_INTERRUPT: 0x00000001 (EN_Guaranteed_Perf_Change, Dis_Excursion_Min)
cpu0: MSR_HWP_STATUS: 0x00000000 (No-Guaranteed_Perf_Change, No-Excursion_Min)

Signed-off-by: Len Brown <len.brown@intel.com>
(cherry picked from commit 7f5c258e1ce1e0909d3195694ac79f143051e513)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>
Acked-by: Kamal Mostafa <kamal@canonical.com>