cadence_ttc: changed master clock frequency

Change the timer clock frequency to 133MHz which is correct. the old 2.5MHz
value was for the pre-silicon emulation platform.
Signed-off-by: NPeter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/cadence_ttc.c

@@ -405,7 +405,7 @@ static int cadence_ttc_init(SysBusDevice *dev)
     int i;
 
     for (i = 0; i < 3; ++i) {
-        cadence_timer_init(2500000, &s->timer[i]);
+        cadence_timer_init(133000000, &s->timer[i]);
         sysbus_init_irq(dev, &s->timer[i].irq);
     }