First init.

libraries/Adafruit_BusIO/CMakeLists.txt

@@ -0,0 +1,11 @@
+# Adafruit Bus IO Library
+# https://github.com/adafruit/Adafruit_BusIO
+# MIT License
+
+cmake_minimum_required(VERSION 3.5)
+
+idf_component_register(SRCS "Adafruit_I2CDevice.cpp" "Adafruit_BusIO_Register.cpp" "Adafruit_SPIDevice.cpp" 
+                       INCLUDE_DIRS "."
+                       REQUIRES arduino)
+
+project(Adafruit_BusIO)