It looks like this is not needed, or in need of being updated as a bunch of other lines in prologue.rpy have changed. The better way would be to use the attached script.rpy which has the line
replaced with
I didn't do a full search of all the game files but in a cursory attempt I only found a check for inc_patch in prologue.rpy above the line you deleted. If the dev decides to do more extensive line replacements keyed from that variable, changing the assign seems like the best way to go.
As always, delete the xxxxx_ in front of the file name, extract and put in the game folder.