Improve compatibility with ARM Compiler V6 with C++98 mode (#1788)
Improve compatibility with ARM Compiler V6 with C++98 mode (#1788)

* Fixed infinite loop during calculation size of lv_list

* Fixed msvc 2019 compiler error C4576 when using the LVGL inside C++ code

* Refactoring to make autocomplete less noisy

* Improve compatibility with ARM Compiler V6 with C++98 mode

* Replaced non-ascii symbol

* Fixed CI build error

* Refactoring, added ability to override _LV_COLOR_HAS_MODERN_CPP
littlevgl/lvgl,littlevgl/lvgl,littlevgl/lvgl,littlevgl/lvgl