arm: vt8500: Convert irq.c for multiplatform integration

This patch converts arch-vt8500/irq.c to MULTI_IRQ_HANDLER and
SPARSE_IRQ. IRQ domain is changed from legacy to linear.

Also, remove legacy code in include/mach/entry-macro.S and
include/mach/irq.h to prepare for multiplatform.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/arm/mach-vt8500/vt8500.c b/arch/arm/mach-vt8500/vt8500.c
index 8d3871f..14def0f 100644
--- a/arch/arm/mach-vt8500/vt8500.c
+++ b/arch/arm/mach-vt8500/vt8500.c
@@ -194,5 +194,6 @@
 	.timer		= &vt8500_timer,
 	.init_machine	= vt8500_init,
 	.restart	= vt8500_restart,
+	.handle_irq	= vt8500_handle_irq,
 MACHINE_END