Zipit Z2 kernel

Recently I did some stuff for Z2 kernel:
  • fixed bug in libertas (already submitted patches upstream)
  • added proper suspend/resume support for libertas
  • fixed wrong coefficient to convert adc value to battery voltage
  • fixed bug in Z2 ASoC driver (with detecting Z2 soundcard)
  • make Z2 resume only on power button and AC plug
Patches agains Marex's tree you can find here. cpufreq and cpu voltage regulator do not work, so don't enable them in kernel config.

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