Don't trigger an interrupt when cb = -1.
Count cycles in the GPU, rough guess at timing.

Doesn't actually do anything yet with the count, though.
Always trigger FINISH and SIGNAL from END.
Handle displaylist state more like the PSP.

All these changes from Orphis' hard work.  Things still looking good.
Return more correct values in sceGeDrawSync().
Don't actually run sceGeListEnqueueHead right away.
Implement sceGeBreak()/sceGeContinue().
Merge pull request #1174 from unknownbrackets/dlist-parts

More of Orphis' dlist rewrite (continue/break, status, errors)