I actually know someone who had their full name listed as last name (and no given names) on one of their permits or a visa. CIC do indeed commit these stupid mistakes more often than you think. They had it corrected back then IIRC (though it was months later and even reentered with it).That explains why your TRV was issued the way it was issued
For OP, just FYI looks to me that if you call someone they'll tell you to contact CIC and correct it. This is probably the kind of situation where your best chance is not to ask in advance if you wanna do it.
I'd call CIC and see what they say, since you're in Canada and can get a human on the phone.