clocksource: of: Respect device tree node status

Clocksource devices provided by DT can be disabled (status != "okay").
Instead of registering clocksource drivers for disabled nodes, respect
the device's status by skiping disabled nodes.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c
index 37f5325..b9ddd9e 100644
--- a/drivers/clocksource/clksrc-of.c
+++ b/drivers/clocksource/clksrc-of.c
@@ -30,6 +30,9 @@
 	clocksource_of_init_fn init_func;
 
 	for_each_matching_node_and_match(np, __clksrc_of_table, &match) {
+		if (!of_device_is_available(np))
+			continue;
+
 		init_func = match->data;
 		init_func(np);
 	}