Incompatibility with recent LVGL

[AnthoJack]

Errors appear when trying to compile new versions of LVGL on SO3. They are due to 2 lines in the usr/lib/lv_conf.h file:

• line 16: #include <stdint.h>
• line 210: typedef void * lv_user_data_t;

The *lv_conf.h" file is eventually included in assembly code files. The 2 lines are/contain typedef directives that the assembly compiler does not understand. Removing them altogether allows LVGL to build successfully. The demo applications found in usr/src however aren't compatible with the newer versions of LVGL and generate errors

Suggestion: Now would probably be a good time to introduce LVGL as a submodule of SO3 to remove the need to align LVGL manually