Allow using TrueType fonts LVGL. Based on https://github.com/nothings/stb
When enabled in `lv_conf.h` with `LV_USE_TINY_TTF``lv_tiny_ttf_create_data(data, data_size, line_height)` can be used to create a TTF font instance at the specified line height. You can then use that font anywhere `lv_font_t` is accepted.
By default, the TTF or OTF file must be embedded as an array, either in a header, or loaded into RAM in order to function.
However, if `LV_TINY_TTF_FILE_SUPPORT` is enabled, `lv_tiny_ttf_create_file(path, line_height)` will also be available, allowing tiny_ttf to stream from a file. The file must remain open the entire time the font is being used.
After a font is created, you can change the size by using `lv_tiny_ttf_set_size(font, line_height)`.
By default, a font will use up to 4KB of cache to speed up rendering glyphs. This maximum can be changed by using `lv_tiny_ttf_create_data_ex(data, data_size, line_height, cache_size)` or `lv_tiny_ttf_create_file_ex(path, line_height, cache_size)` (when available). The cache size is indicated in bytes.
