arm64: Move intr_pic_init_secondary earlier

This may have been called after intr_irq_shuffle. For most interrupt
controllers this appears to be safe, however for the GICv5 we need to
read a per-CPU ID register before we can assign interrupts to a given
CPU.

Fix the race by moving intr_pic_init_secondary earlier in the boot,
after devices have been enumerated and before the interrupts are moved
to their assigned CPUs.

Sponsored by:	Arm Ltd
Differential Revision:	https://reviews.freebsd.org/D53685

sys/arm64/arm64/mp_machdep.c

@@ -270,6 +270,8 @@ init_secondary(uint64_t cpu)
 	install_cpu_errata();
 	enable_cpu_feat(CPU_FEAT_AFTER_DEV);
 
+	intr_pic_init_secondary();
+
 	/* Signal we are done */
 	atomic_add_int(&aps_started, 1);
 
@@ -288,8 +290,6 @@ init_secondary(uint64_t cpu)
 	    ("pmap0 doesn't match cpu %ld's ttbr0", cpu));
 	pcpup->pc_curpmap = pmap0;
 
-	intr_pic_init_secondary();
-
 	/* Start per-CPU event timers. */
 	cpu_initclocks_ap();