Don't call memset to clean irq_desc; these data fields have already

previously been initialized statically in kernel/irq/handle.c.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/au1000/common/irq.c

@@ -446,7 +446,6 @@ void __init arch_init_irq(void)
 	extern int au1xxx_ic0_nr_irqs;
 
 	cp0_status = read_c0_status();
-	memset(irq_desc, 0, sizeof(irq_desc));
 	set_except_vector(0, au1000_IRQ);
 
 	/* Initialize interrupt controllers to a safe state.

arch/mips/ite-boards/generic/irq.c

@@ -181,7 +181,6 @@ void __init arch_init_irq(void)
 	int i;
         unsigned long flags;
 
-        memset(irq_desc, 0, sizeof(irq_desc));
         set_except_vector(0, it8172_IRQ);
 
 	/* mask all interrupts */