Function lv_cache_set_create_cb 

pub unsafe extern "C" fn lv_cache_set_create_cb(
    cache: *mut lv_cache_t,
    alloc_cb: lv_cache_create_cb_t,
    user_data: *mut c_void,
)

Set the create callback of the cache. @param cache The cache object pointer to set the create callback. @param alloc_cb The create callback to set. @param user_data A user data pointer.