changes for i2c lib

common/pimoroni_i2c.cmake

@@ -0,0 +1,11 @@
+set(LIB_NAME pimoroni_i2c)
+add_library(${LIB_NAME} INTERFACE)
+
+target_sources(${LIB_NAME} INTERFACE
+    ${CMAKE_CURRENT_LIST_DIR}/${LIB_NAME}.cpp
+)
+
+target_include_directories(${LIB_NAME} INTERFACE ${CMAKE_CURRENT_LIST_DIR})
+
+# Pull in pico libraries that we need
+target_link_libraries(${LIB_NAME} INTERFACE pico_stdlib hardware_i2c)