Add INTR_TYPE_AV so that we can get to the PI_AV priority in the ithread

handlers.  This is beneficial since it means that pcm's MPSAFE handler
can get run before things that will block on Giant in the shared irq
case.

sys/kern/kern_intr.c

@@ -76,7 +76,7 @@ ithread_priority(enum intr_type flags)
 	u_char pri;
 
 	flags &= (INTR_TYPE_TTY | INTR_TYPE_BIO | INTR_TYPE_NET |
-	    INTR_TYPE_CAM | INTR_TYPE_MISC | INTR_TYPE_CLK);
+	    INTR_TYPE_CAM | INTR_TYPE_MISC | INTR_TYPE_CLK | INTR_TYPE_AV);
 	switch (flags) {
 	case INTR_TYPE_TTY:
 		pri = PI_TTYLOW;
@@ -94,6 +94,9 @@ ithread_priority(enum intr_type flags)
 	case INTR_TYPE_CAM:
 		pri = PI_DISK;          /* XXX or PI_CAM? */
 		break;
+	case INTR_TYPE_AV:		/* Audio/video */
+		pri = PI_AV;
+		break;
 	case INTR_TYPE_CLK:
 		pri = PI_REALTIME;
 		break;

sys/sys/bus.h

@@ -88,6 +88,7 @@ enum intr_type {
 	INTR_TYPE_CAM = 8,
 	INTR_TYPE_MISC = 16,
 	INTR_TYPE_CLK = 32,
+	INTR_TYPE_AV = 64,
 	INTR_FAST = 128,
 	INTR_EXCL = 256,		/* exclusive interrupt */
 	INTR_MPSAFE = 512,		/* this interrupt is SMP safe */