don't parse firmware as an MSE on the n3g

[lemonjesus]

the n3g's firmware is not an MSE package. trying to parse it as one on an n3g restore will cause it to not accept the firmware payload because the reported payload size is different.

[lemonjesus]

I'm being told that the n3g's firmware is in fact, an MSE file. I was led astray by the fact that skipping parsing worked. I'll continue to use this fix on my branch, and open an issue here because it's not parsing correctly so I or someone else can look into it later.