Remove compiler warning for typedef'ed generic compare function and its specific implementation

[devprabal]

Branch: https://github.com/devprabal/small-linklist/tree/develop

main.c:69:26: warning: initialization of ‘_Bool (*)(void *, void *)’ from incompatible pointer type ‘_Bool (*)(Person *, Person *)’ [-Wincompatible-pointer-types]
   69 |     [ITEM_TYPE_PERSON] = compare_person,
      |                          ^~~~~~~~~~~~~~
main.c:69:26: note: (near initialization for ‘compare_item_func_list[0]’)

However, you should neither change find_in_list() nor compare_person().
You can create new data structure and/or functions, and change other implementations, if you want.