clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map()

Let's use the of_io_request_and_map() API so that the frame
region is protected and shows up in /proc/iomem.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>

drivers/clocksource/arm_arch_timer.c

@@ -971,8 +971,9 @@ static int __init arch_timer_mem_init(struct device_node *np)
 	}
 
 	ret= -ENXIO;
-	base = arch_counter_base = of_iomap(best_frame, 0);
-	if (!base) {
+	base = arch_counter_base = of_io_request_and_map(best_frame, 0,
+							 "arch_mem_timer");
+	if (IS_ERR(base)) {
 		pr_err("arch_timer: Can't map frame's registers\n");
 		goto out;
 	}