ARM: realview/versatile: update clock source registration

In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new
interfaces were added which simplify (and optimize) the selection of the
divisor shift/mult constants.  Switch over to using this new interface.
Tested-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/plat-versatile/timer-sp.c

@@ -46,7 +46,6 @@ static struct clocksource clocksource_sp804 = {
 	.rating		= 200,
 	.read		= sp804_read,
 	.mask		= CLOCKSOURCE_MASK(32),
-	.shift		= 20,
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
@@ -63,8 +62,7 @@ void __init sp804_clocksource_init(void __iomem *base)
 	writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
 		clksrc_base + TIMER_CTRL);
 
-	cs->mult = clocksource_khz2mult(TIMER_FREQ_KHZ, cs->shift);
-	clocksource_register(cs);
+	clocksource_register_khz(cs, TIMER_FREQ_KHZ);
 }