Not only getting rid of the "useless" (and thankfully, consistent)
bitplane parameter, but also allowing those shortened macros to be
redefined for the upcoming little ZUN inconsistency.
Part of P0120, funded by Yanga.
The usual case where ZUN should have just written a custom EGC-powered
unblitter, instead of resorting to the word-aligned rectangle one…
Part of P0120, funded by Yanga.