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>
diff --git a/arch/arm/mach-ixp4xx/common.c b/arch/arm/mach-ixp4xx/common.c
index f4656d2..1e93dfe 100644
--- a/arch/arm/mach-ixp4xx/common.c
+++ b/arch/arm/mach-ixp4xx/common.c
@@ -401,7 +401,7 @@
 /*
  * clocksource
  */
-cycle_t ixp4xx_get_cycles(void)
+cycle_t ixp4xx_get_cycles(struct clocksource *cs)
 {
 	return *IXP4XX_OSTS;
 }