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-at91/board-cpu9krea.c

@@ -374,7 +374,7 @@ MACHINE_START(CPUAT9260, "Eukrea CPU9260")
 MACHINE_START(CPUAT9G20, "Eukrea CPU9G20")
 #endif
 	/* Maintainer: Eric Benard - EUKREA Electromatique */
-	.timer		= &at91sam926x_timer,
+	.init_time	= at91sam926x_pit_init,
 	.map_io		= at91_map_io,
 	.handle_irq	= at91_aic_handle_irq,
 	.init_early	= cpu9krea_init_early,