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>
diff --git a/arch/arm/mach-footbridge/isa-timer.c b/arch/arm/mach-footbridge/isa-timer.c
index c40bb41..d9301dd 100644
--- a/arch/arm/mach-footbridge/isa-timer.c
+++ b/arch/arm/mach-footbridge/isa-timer.c
@@ -31,14 +31,10 @@
 	.dev_id		= &i8253_clockevent,
 };
 
-static void __init isa_timer_init(void)
+void __init isa_timer_init(void)
 {
 	clocksource_i8253_init();
 
 	setup_irq(i8253_clockevent.irq, &pit_timer_irq);
 	clockevent_i8253_init(false);
 }
-
-struct sys_timer isa_timer = {
-	.init		= isa_timer_init,
-};