Added support for SugarCube device

Author: Ihor Mishchenko

variants/esp32/sugarcube/platformio.ini

@@ -0,0 +1,8 @@
+[env:sugarcube]
+extends = esp32_base
+board = ttgo-lora32-v21
+board_check = true
+build_flags = 
+  ${esp32_base.build_flags} -D TLORA_V2_1_16 -I variants/esp32/sugarcube
+  -DGPS_POWER_TOGGLE ; comment this line to disable triple press function on the user button to turn off gps entirely.
+upload_speed = 115200

variants/esp32/sugarcube/variant.h

@@ -0,0 +1,26 @@
+#define BATTERY_PIN 35
+#define ADC_CHANNEL ADC1_GPIO35_CHANNEL
+#define BATTERY_SENSE_SAMPLES 30
+
+// ratio of voltage divider = 2.0 (R42=100k, R43=100k)
+#define ADC_MULTIPLIER 2
+
+#define I2C_SDA 21 // I2C pins for this board
+#define I2C_SCL 22
+
+#define BUTTON_PIN 0
+//#define LED_PIN 25 // If defined we will blink this LED
+
+#define USE_RF95
+#define LORA_DIO0 26 // a No connect on the SX1262 module
+#define LORA_RESET 23
+
+// In the T3 V1.6.1 TXCO version, GPIO 33 is connected to Radio’s
+// internal temperature-compensated crystal oscillator enable
+#ifdef LORA_TCXO_GPIO
+#define LORA_DIO1 RADIOLIB_NC // no-connect on sx127x module
+#else
+#define LORA_DIO1 33 // https://www.thethingsnetwork.org/forum/t/big-esp32-sx127x-topic-part-3/18436
+#endif
+
+#define LORA_DIO2 32 // Not really used