I need to hook and change language of facebook sdk

Check the documentation of add_filter() first argument is name of filter and second one is callback function name. (both are required)

See the example for your case:-

add_filter('bimber_facebook_sdk_src', 'change_fb_sdk_url');
function change_fb_sdk_url($current_url) {
    // Variable $current_url hold the current value of URL
    // You can manipulate what you want
    // Or simply return your URL

    return '//url_you_want';
}

Please note:- filter callback function must return the value!