Pokémon R/B: Fix incompatible option combination

[Alchav]

What is this fixing or adding?

You can set fossil_check_item_types to no_key_items but then turn key_items_only on, resulting in no non-key-items to fill the fossil checks. This skips processing the fossil_check_item_types rules at all if key_items_only is on

How was this tested?

Generating with same seed # of a previously failing generation

[ScipioWright]

Suggested change

	if not self.multiworld.key_items_only[self.player]:
	if self.multiworld.fossil_check_item_types[self.player] == "key_items":
	if not self.multiworld.key_items_only[self.player]:
	rule = None
	if self.multiworld.fossil_check_item_types[self.player] == "key_items":

Need to establish rule before using it. None isn't necessarily the correct thing to choose here though, I'm just not super sure what is without reviewing the code further.

[NewSoupVi]

Another option would be to actually have an "else:" case, in which case declaring it before becomes unnecessary. Technically, even the current code is only wrong because a case was hit that wasn't covered, although that is exactly the reason why you usually shouldn't do this unless you have an "else:"

(For the record: Block scope is not a thing in Python.)

[ScipioWright]

Ahh right, I forgot python is nice like that, letting you have it if every case leads you to setting rule as something