Merge pull request #131 from johnboiles/master

For ESP-IDF builds use arduino-esp32 instead of arduino dependency

Author: ladyada

CMakeLists.txt

@@ -6,6 +6,6 @@ cmake_minimum_required(VERSION 3.5)
 
 idf_component_register(SRCS "Adafruit_I2CDevice.cpp" "Adafruit_BusIO_Register.cpp" "Adafruit_SPIDevice.cpp" 
                        INCLUDE_DIRS "."
-                       REQUIRES arduino)
+                       REQUIRES arduino-esp32)
 
 project(Adafruit_BusIO)