Addw2 support (#67)

* Add addw2 board

* Set charge params and update gpio.h

* Set VGA fan to 100% when entering scratch rom

* Implement keyboard LEDs

* Turn off keyboard LEDs in gpio defaults

* Default airplane mode LED to off

* Enable GPU power and fan control

* Add NVIDIA GPU power and temp to power.csv

* Add NVIDIA GPU fan value to power.sh

* Move GPU init back to coreboot

* Do not turn on GPU fan if GPU is off

* Show POST codes

* Add timestamps to console_external

* Accept port 81 cycles

* Move setting RSTS into ec_init

* Move post code debugging to system76/common

* Move some GPIO init from system76/common to boards

* Make some power signals optional

* Remove POST code support - it only works on IT5570

src/board/system76/common/kbc.c

@@ -21,6 +21,8 @@ bool kbc_second = false;
 // Translate from scancode set 2 to scancode set 1
 // for basically no good reason
 static bool kbc_translate = true;
+// LED state
+uint8_t kbc_leds = 0;
 
 // Values from linux/drivers/input/keyboard/atkbd.c
 static const uint16_t kbc_typematic_period[32] = {
@@ -256,6 +258,7 @@ void kbc_event(struct Kbc * kbc) {
                 case KBC_STATE_SET_LEDS:
                     TRACE("  set leds\n");
                     state = KBC_STATE_NORMAL;
+                    kbc_leds = data;
                     kbc_keyboard(kbc, 0xFA, KBC_TIMEOUT);
                     break;
                 case KBC_STATE_SCANCODE: