ARM: delete struct sys_timer

Now that the only field in struct sys_timer is .init, delete the struct,
and replace the machine descriptor .timer field with the initialization
function itself.

This will enable moving timer drivers into drivers/clocksource without
having to place a public prototype of each struct sys_timer object into
include/linux; the intent is to create a single of_clocksource_init()
function that determines which timer driver to initialize by scanning
the device dtree, much like the proposed irqchip_init() at:
http://www.spinics.net/lists/arm-kernel/msg203686.html

Includes mach-omap2 fixes from Igor Grinberg.

Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

arch/arm/mach-sa1100/time.c

@@ -117,7 +117,7 @@ static struct irqaction sa1100_timer_irq = {
 	.dev_id		= &ckevt_sa1100_osmr0,
 };
 
-static void __init sa1100_timer_init(void)
+void __init sa1100_timer_init(void)
 {
 	writel_relaxed(0, OIER);
 	writel_relaxed(OSSR_M0 | OSSR_M1 | OSSR_M2 | OSSR_M3, OSSR);
@@ -137,7 +137,3 @@ static void __init sa1100_timer_init(void)
 		clocksource_mmio_readl_up);
 	clockevents_register_device(&ckevt_sa1100_osmr0);
 }
-
-struct sys_timer sa1100_timer = {
-	.init		= sa1100_timer_init,
-};