ARM: provide a late_initcall hook for platform initialization

This allows platforms to set up things that need to be done at
late_initcall time.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Robert Lee <rob.lee@linaro.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/include/asm/mach/arch.h

@@ -43,6 +43,7 @@ struct machine_desc {
 	void			(*init_irq)(void);
 	struct sys_timer	*timer;		/* system tick timer	*/
 	void			(*init_machine)(void);
+	void			(*init_late)(void);
 #ifdef CONFIG_MULTI_IRQ_HANDLER
 	void			(*handle_irq)(struct pt_regs *);
 #endif