ARM: pxa: remove NR_IRQS

Remove NR_IRQS and add a per machine .nr_irqs setting.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
diff --git a/arch/arm/mach-pxa/time.c b/arch/arm/mach-pxa/time.c
index b503049..3d6c9bd 100644
--- a/arch/arm/mach-pxa/time.c
+++ b/arch/arm/mach-pxa/time.c
@@ -22,6 +22,7 @@
 #include <asm/mach/time.h>
 #include <asm/sched_clock.h>
 #include <mach/regs-ost.h>
+#include <mach/irqs.h>
 
 /*
  * This is PXA's sched_clock implementation. This has a resolution