[lua] Correct isValidEntry logic to trade for registration

[MowFord]

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What does this pull request do?

Closes #5613 .

The isValidEntry logic was referencing the battlefield entryNpc value (which never explicitly gets set, it gets passed and used to build a table of one entry for entryNpcs) instead of the traded npc's name

Steps to test these changes

Give yourself all the key items and items and trade the 4 chips to the swirling vortex

[WinterSolstice8]

Makes sense, apollyon has multiple entrances for this

[claywar]

for _, npcName in self.entryNpcs do
    if npc:getName == npcName then
        return true
    end

    return false
end

[claywar]

entryNpcs is a table, entryNpc on construct is now converted to a table, so this was a miss on my part

[claywar]

Also set entryNpcs in the constructor to { '_12i, '_127' }

[claywar]

Most likely now that I think of it, you won't even need the entry function in this BCNM

[MowFord]

Got it, so for both we just need to remove the isvalidentry override and defined entryNpcs in their constructors?

[claywar]

I believe so. Sorry for the mixed info as I was thinking through things, but yeah, that should work on its own. Added support for multiple entrances with Divine Might, so the same logic should work here I think

[MowFord]

Yep, simpler logic and it works.

Really love the new battlefield content structure. Easy to module changes, cleaner format, more things in one place

Dismissed because I wrongly assumed the system didn't support multiple entrances

[WinterSolstice8]

A lot more elegant