C++ conversion (#80)

Converted project to C++

Libraries/lv_screenshot/CMakeLists.txt

@@ -0,0 +1,30 @@
+cmake_minimum_required(VERSION 3.16)
+
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+file(GLOB SOURCES "src/*.c*")
+file(GLOB HEADERS "src/*.h*")
+
+add_library(lv_screenshot STATIC)
+
+target_sources(lv_screenshot
+    PRIVATE ${SOURCES}
+    PUBLIC ${HEADERS}
+)
+
+target_include_directories(lv_screenshot
+    PRIVATE private
+    PUBLIC src
+)
+
+if (DEFINED ENV{ESP_IDF_VERSION})
+    target_link_libraries(lv_screenshot
+        PUBLIC idf::lvgl
+    )
+else()
+    target_link_libraries(lv_screenshot
+        PUBLIC lvgl
+    )
+endif()