Modifying logo-slider.php and child themes

Hi,
I made two minor changes on theses functions :
wp_logo_settings_admin()
logo_slider($args = array(), $content = null)

Basicaly I added a ninth item in the combobox that specifies the number of shown logos and secondly I allowed this amount in iPads and Android devices.

I wish I could put in a way theses changes in my child theme. At worst, I would like to put all the php file.
I’m new about hooking functions but it seems that theses functions are not “hookable”.

Any help would be much appreciated !

Thank you