some more ports from MAME

git-svn-id: svn://svn.code.sf.net/p/pinmame/code/trunk@3578 6f51dfdd-75df-4273-8f3b-818b1e6aa8bf
wire up YM2610 flag

..unused but at least equal to MAME then

git-svn-id: svn://svn.code.sf.net/p/pinmame/code/trunk@3579 6f51dfdd-75df-4273-8f3b-818b1e6aa8bf
include (undef'd) decapped chip values again

git-svn-id: svn://svn.code.sf.net/p/pinmame/code/trunk@3580 6f51dfdd-75df-4273-8f3b-818b1e6aa8bf
more ports from MAME

git-svn-id: svn://svn.code.sf.net/p/pinmame/code/trunk@3581 6f51dfdd-75df-4273-8f3b-818b1e6aa8bf
port more MAME changes

..this could fix weird sounding OKIM6376 (i tried to make it similar to MAME)

git-svn-id: svn://svn.code.sf.net/p/pinmame/code/trunk@3582 6f51dfdd-75df-4273-8f3b-818b1e6aa8bf
use correct number of channels in sn76496 sound clipping prevention code

git-svn-id: svn://svn.code.sf.net/p/pinmame/code/trunk@3583 6f51dfdd-75df-4273-8f3b-818b1e6aa8bf