Fix secondary PIC initialization order

Call arm_init_secondary before any other PIC-related functions
are called. This is necessary for GICv3 where PIC_INIT_SECONDARY
allocates resources needed for all further operations.

Obtained from: Semihalf
Sponsored by:  The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3066

sys/arm64/arm64/mp_machdep.c

@@ -229,6 +229,9 @@ init_secondary(uint64_t cpu)
 	pcpup->pc_curthread = pcpup->pc_idlethread;
 	pcpup->pc_curpcb = pcpup->pc_idlethread->td_pcb;
 
+	/* Configure the interrupt controller */
+	arm_init_secondary();
+
 	for (i = 0; i < COUNT_IPI; i++)
 		arm_unmask_ipi(i);
 
@@ -239,9 +242,6 @@ init_secondary(uint64_t cpu)
 	vfp_init();
 #endif
 
-	/* Configure the interrupt controller */
-	arm_init_secondary();
-
 	/* Enable interrupts */
 	intr_enable();