Applied all mainline PCem commits;

Removed SCSI thread waiting (except after executing the READ SUBCHANNEL command, to alleviate the effects of READ SUBCHANNEL spam done by CD players).

src/timer.c

@@ -95,7 +95,7 @@ void timer_update_outstanding(void)
 		if (*timers[c].enable && *timers[c].count < timer_latch)
 			timer_latch = *timers[c].count;
 	}
-	timer_count = timer_latch = (timer_latch + ((1 << TIMER_SHIFT) - 1)) >> TIMER_SHIFT;
+	timer_count = timer_latch = (timer_latch + ((1 << TIMER_SHIFT) - 1));
 }