ARM: SMP: consolidate trace_hardirqs_off() into common SMP code

All platforms call trace_hardirqs_off() in their secondary startup code,
so move this into the core SMP code - it doesn't need to be in the
per-platform code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index c66f2d3..a30c409 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -317,6 +317,7 @@
 
 	cpu_init();
 	preempt_disable();
+	trace_hardirqs_off();
 
 	/*
 	 * Give the platform a chance to do its own initialisation.