Make clocksource name const

As nothing should be writing to the clocksource name string, make the
clocksource name pointer const.  Build-tested on ARM Versatile Express.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: John Stultz <johnstul@us.ibm.com>

include/linux/clocksource.h

@@ -161,7 +161,7 @@ struct clocksource {
 	/*
 	 * First part of structure is read mostly
 	 */
-	char *name;
+	const char *name;
 	struct list_head list;
 	int rating;
 	cycle_t (*read)(struct clocksource *cs);