One way or another, +6, but you have to talk to your GM about this
In this personal case the DM asked her to spend 1 feat to take Psionic Talent, not automatic.
Your GM has changed the rules, and the answer to your question hinges entirely on what it means when the GM says this. Do you still have the original Wild Talent feat? Or did you lose that feat here as part of the upgrade? (And if so, why? You could have just taken Psionic Talent for the same feat slot and left Wild Talent alone.)
Normally, you would lose Wild Talent when you get Psionic Talent, so you wouldn’t get 2 power points from it any more—you would get 2 power points from Psionic Talent instead. You could then take Wild Talent (which you no longer have) in order to get Unlocked Talent (and get +2 from each, so total +6).
Alternatively, if you don’t lose Wild Talent when getting Psionic Talent—and you shouldn’t, if you have to spend another feat on it—then you can’t take it again, but also don’t have to. So you still end up with +6, but you save a feat because you didn’t have to get Wild Talent again.
So +6 either way, but you have to sort out how many feats were required to get there.
You should never have to spend remotely this many feats for empty mind
Unlocked Talent should allow Psionic Talent to fulfill its prerequisite. Really, there never should have been separate Wild Talent and Psionic Talent feats at all; it should have just been one feat the whole time. Having Psionic Talent should never bar you from anything Wild Talent allows, and vice versa.
The reason things were written the way they are is because psionic classes were sort of assumed to be manifesters, and manifesters should be taking Expanded Knowledge instead of Unlocked Talent: it’s a far better feat for them. The issue of non-manifesting psionic classes seeking Unlocked Talent was never considered, and this causes a lot of needless problems for the aegis and soulknife and so on.
You should be able to just take Unlocked Talent and get empty mind with no other feats. Naturally psionic should provide all of the requirements you need, and this should be a 1-feat investment. You are talking about spending something like three separate feats, and that is simply wrong—that is an utterly massive investment, and you’re getting almost nothing out of it. Empty mind isn’t even that good.
Note: I have worked on Dreamscarred Press’s psionics
Both as a disclaimer and as a way of backing up the answers and recommendations in this question, I want to point out that I have worked for Dreamscarred Press on psionic material. I didn’t work on Ultimate Psionics—if I had I would have pushed for combining Wild Talent and Psionic Talent to begin with—but I wrote a fair amount of later material for them. I was hired on the basis of my expertise with this material. I strongly recommend not making a big deal out of Wild Talent vs. Psionic Talent. They are, practically speaking, the same feat, and should be treated as such in the few corner cases where a distinction is made—because I can almost certainly assure you that the distinction was made in error.