document remainder of secret_base scripts, delete unneeded scripts.incs

src/field_control_avatar.c

@@ -355,7 +355,7 @@ static const u8 *GetInteractedBackgroundEventScript(struct MapPosition *position
         {
             gSpecialVar_0x8004 = bgEvent->bgUnion.secretBaseId;
             if (TrySetCurSecretBase())
-                return EventScript_2759F1;
+                return SecretBase_EventScript_CheckEntrance;
         }
         return NULL;
     }