First pass at tidying up ide interface. It no longer tries to force everything to act as a PC. A copy of the VIA VT83C461 datasheet would be useful to remove some of the hacks added to make the games using it work again. [smf]

git-svn-id: svn://dspnet.fr/mame/trunk@23541 749742ba-7341-0410-aadc-df50b521781e