Function register_log_level_changed_callback 

pub unsafe extern "C" fn register_log_level_changed_callback(
    handle: &Context,
    callback: Option<LogLevelChangedCallback>,
) -> ReturnValue

Register callback function called when log level of context was changed.

• @param handle pointer to an object containing information about one special logging context.
• @param (*dlt_log_level_changed_callback) function pointer to callback function
• @return Value from DltReturnValue enum