No, you cannot say that “it suffices the condition”. That is not English.
The author is saying that “it is enough that f(z) have a primitive in a region Ω” for such and such a thing to be satisfied or hold true or apply. Something like that.
Note that we have moved into the hypothetical havens of that rarefied domain known as the subjunctive: “if suffices that the function have a primitive”. Only the very most careful of speakers (or writers) speak that way any more. But in this domain, it remains commonplace and indeed even expected. It is how things are done there.
That’s because mathematicians are even more precise than lawyers. These use language extremely — even exceedingly — carefully. When I was doing corpus studies of modern uses of the English subjunctive, mathematics treatises were the richest gold mine to be found for such rarities as these.
Mathematicians are exquisitely formal people, you know, when it comes to language use. It comes from having to formally define things as they artfully create their mathematics. This author wrote exactly what he meant to write. You must come to understand what it means, not try to rewrite it; otherwise you risk destroying what he has so carefully crafted.
tl;dr: Suffice it to say, suffice is not transitive.