[ARM] More sparse fixes

arch/arm/kernel/irq.c:998:26: warning: Using plain integer as NULL pointer
arch/arm/kernel/smp.c:145:25: warning: Using plain integer as NULL pointer
arch/arm/kernel/smp.c:362:5: warning: symbol 'smp_call_function_on_cpu' was not declared. Should it be static?
drivers/video/amba-clcd.c:521:12: warning: symbol 'amba_clcdfb_init' was not declared. Should it be static?

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/irq.c

@@ -995,7 +995,7 @@ void __init init_irq_proc(void)
 	struct proc_dir_entry *dir;
 	int irq;
 
-	dir = proc_mkdir("irq", 0);
+	dir = proc_mkdir("irq", NULL);
 	if (!dir)
 		return;
 

arch/arm/kernel/smp.c

@@ -515,7 +515,7 @@ static void ipi_cpu_stop(unsigned int cpu)
  *
  *  Bit 0 - Inter-processor function call
  */
-void do_IPI(struct pt_regs *regs)
+asmlinkage void do_IPI(struct pt_regs *regs)
 {
 	unsigned int cpu = smp_processor_id();
 	struct ipi_data *ipi = &per_cpu(ipi_data, cpu);

drivers/video/amba-clcd.c

@@ -518,7 +518,7 @@ static struct amba_driver clcd_driver = {
 	.id_table	= clcdfb_id_table,
 };
 
-int __init amba_clcdfb_init(void)
+static int __init amba_clcdfb_init(void)
 {
 	if (fb_get_options("ambafb", NULL))
 		return -ENODEV;