Very unfortunate that this has to go into the overlay translation unit
due to the upcoming functions near-calling the `far overlay_wipe()`
function.
Part of P0279, funded by Yanga and Blue Bolt.
Oh look, a small TH02-only commit! Might as well decompile the small
function in front of TH02's overlay_wipe(), so that I can include it
in the next commit.
Part of P0225, funded by Enderwolf, Blue Bolt, 32th System, and Yanga.
nmlgc