the message indicates that indeed your Raspberry Pi is not compatible with the distribution of nodejs mentioned in the tutorial.
Unfortunately I don't know of any pre-compiled distribution compatibble with the armv6 processor... the Raspbian repo has a version of node js but it is so outdated that I highly doubt that you'd get any further with the tutorial/homebridge.
... I'll flag it to @sandyjmacdonald as I think it would be worth mentioning in the tutorial that this is only compatible with the Pi2/Pi3. Sorry about that!
PS: you could of course try to compile it from source, but I would highly advise not to try, this will be a gruesome and long process that I'm not even would get you anywhere useful, though in theory it should be possible.
PS2: I see that Sandy mentions the Pi3 as an assumed underlying hardware mid-way through the tutorial, though a clarification right on the onset would avoid any disappointment or puzzlement.