clocksource: pass clocksource to read() callback

Pass clocksource pointer to the read() callback for clocksources.  This
allows us to share the callback between multiple instances.

[hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mach-ns9xxx/time-ns9360.c

@@ -25,7 +25,7 @@
 #define TIMER_CLOCKEVENT 1
 static u32 latch;
 
-static cycle_t ns9360_clocksource_read(void)
+static cycle_t ns9360_clocksource_read(struct clocksource *cs)
 {
 	return __raw_readl(SYS_TR(TIMER_CLOCKSOURCE));
 }