This function is called from a few different places in the mobile code,
including from one special that is only executed when the
BattleTowerRoomMenu special returns with a non-zero code.
Since that special causes a blue "error" screen to appear, that looks
the exact same as the one you'd get when trying to connect from the
mobile trade corner/battle colosseum in a Pokémon Center's top floor,
and this function contains a bunch of japanese strings in a jumptable, I
think it's reasonable to assume it should be called
"DisplayMobileError".
All of the functions called by it are prefixed with BattleTowerRoomMenu,
but a bunch of them seem more generic than that, since they're part of
different mobile menus. Also called another menu jumptable
BattleTowerRoomMenu2 for the lack of a better name (only the Yes/No menu
functions are used in western crystal).
The names of the more generic functions should be fixed when we start
labelling other menus.
The former is arguably misleading (as you don’t access the memory location in hl to retrieve the jump location), and is consequently deprecated in newer versions of rgbds.
This fix silences these deprecation warnings.