Moved the PIC-internal variables into pic.c, converted the pic
macros to functions.

The small code changes:
- pic_pending() now also takes into account the pic_irqs_active hack
- disabled the "bad HACK" in sound.c to make it compile


git-svn-id: https://dosemu.svn.sourceforge.net/svnroot/dosemu/trunk@1322 7758b857-130e-0410-ab9c-d8735a528d18