System76 common board directory (#53)

* Move configuration for battery into board.mk

* lemp9: remove tcpm code

* Move touchpad to its own module

* Add kbled_reset to all platforms, move items to run on CPU reset to a function

* Add defines for battery and charger address

* Add I2C_0 export to it5570e

* Move common system76 board functions into src/board/system76/common

src/board/system76/galp3-c/board.c

@@ -0,0 +1,30 @@
+#include <board/battery.h>
+#include <board/board.h>
+#include <board/gctrl.h>
+#include <board/gpio.h>
+
+extern uint8_t main_cycle;
+
+void board_init(void) {
+    RSTS = 0x84;
+}
+
+void board_event(void) {
+    if (main_cycle == 0) {
+        if (gpio_get(&ACIN_N)) {
+            // Discharging (no AC adapter)
+            gpio_set(&LED_BAT_CHG, false);
+            gpio_set(&LED_BAT_FULL, false);
+        } else if (battery_status & 0x0020) {
+            // Fully charged
+            // TODO: turn off charger
+            gpio_set(&LED_BAT_CHG, false);
+            gpio_set(&LED_BAT_FULL, true);
+        } else {
+            // Charging
+            // TODO: detect no battery connected
+            gpio_set(&LED_BAT_CHG, true);
+            gpio_set(&LED_BAT_FULL, false);
+        }
+    }
+}