ARM: shmobile: cpuidle: remove shmobile_enter_wfi prototype

Commit 688036b538974de32ce55be8b0e013b003992abc removed the function
'shmobile_enter_wfi' but we forgot to remove the definition in the header file.

Note this function is just an alias to 'cpu_do_idle()' wrapped into a cpuidle
function callback prototype which already exists with the default WFI state
and the arm_simple_enter function.

Remove the function prototype.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/arm/mach-shmobile/include/mach/common.h

@@ -13,9 +13,6 @@ extern int shmobile_clk_init(void);
 extern void shmobile_handle_irq_intc(struct pt_regs *);
 extern struct platform_suspend_ops shmobile_suspend_ops;
 struct cpuidle_driver;
-struct cpuidle_device;
-extern int shmobile_enter_wfi(struct cpuidle_device *dev,
-			      struct cpuidle_driver *drv, int index);
 extern void shmobile_cpuidle_set_driver(struct cpuidle_driver *drv);
 
 extern void sh7372_init_irq(void);