Windows RT devices upstreaming

• i2c workaround for touchcover;
• L2 cache changes (is it upstreamable?);
• ACPI parking protocol (is it upstreamable?);
  • we should use DMI strings instead of DT compatible
• surface rt dts;
• surface 2 panel driver;
• surface 2 dts;
• ideapad dts;
• tf600t dts;