intrng: call pic_init_secondary on all registered PICs

Almost any PIC registered will want its pic_init_secondary(), whether or
not it is a direct child of the root PIC.  Of PICs supporting child
PICs, only GICv3 ever bothers to call children.  In light of this, simply
go through all registered PICs and call their hook.

This means we no longer need intr_irq_root_dev initialized.  We also
nominally need the pic_list_lock held (seems unlikely to matter).

Differential Revision: https://reviews.freebsd.org/D40474

sys/arm64/arm64/gic_v3.c

@@ -1096,12 +1096,11 @@ static void
 gic_v3_init_secondary(device_t dev)
 {
 	struct gic_v3_setup_periph_args pargs;
-	device_t child;
 	struct gic_v3_softc *sc;
 	gic_v3_initseq_t *init_func;
 	struct intr_irqsrc *isrc;
 	u_int cpu, irq;
-	int err, i;
+	int err;
 
 	sc = device_get_softc(dev);
 	cpu = PCPU_GET(cpuid);
@@ -1137,11 +1136,6 @@ gic_v3_init_secondary(device_t dev)
 			gic_v3_enable_intr_periph(&pargs);
 		}
 	}
-
-	for (i = 0; i < sc->gic_nchildren; i++) {
-		child = sc->gic_children[i];
-		PIC_INIT_SECONDARY(child);
-	}
 }
 
 static void

sys/kern/subr_intr.c

@@ -1541,15 +1541,12 @@ dosoftints(void)
 void
 intr_pic_init_secondary(void)
 {
+	struct intr_pic *pic;
 
-	/*
-	 * QQQ: Only root PIC is aware of other CPUs ???
-	 */
-	KASSERT(intr_irq_root_dev != NULL, ("%s: no root attached", __func__));
-
-	//mtx_lock(&isrc_table_lock);
-	PIC_INIT_SECONDARY(intr_irq_root_dev);
-	//mtx_unlock(&isrc_table_lock);
+	//mtx_lock(&pic_list_lock);
+	STAILQ_FOREACH(pic, &pic_list, pic_next)
+		PIC_INIT_SECONDARY(pic->pic_dev);
+	//mtx_unlock(&pic_list_lock);
 }
 #endif