hw/timer/npcm7xx_timer: Use new clock_ns_to_ticks()

Use the new clock_ns_to_ticks() function in npcm7xx_timer where
appropriate.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Hao Wu <wuhaotsh@google.com>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210219144617.4782-5-peter.maydell@linaro.org

hw/timer/npcm7xx_timer.c

@@ -138,8 +138,8 @@ static int64_t npcm7xx_timer_count_to_ns(NPCM7xxTimer *t, uint32_t count)
 /* Convert a time interval in nanoseconds to a timer cycle count. */
 static uint32_t npcm7xx_timer_ns_to_count(NPCM7xxTimer *t, int64_t ns)
 {
-    return ns / clock_ticks_to_ns(t->ctrl->clock,
-                                  npcm7xx_tcsr_prescaler(t->tcsr));
+    return clock_ns_to_ticks(t->ctrl->clock, ns) /
+        npcm7xx_tcsr_prescaler(t->tcsr);
 }
 
 static uint32_t npcm7xx_watchdog_timer_prescaler(const NPCM7xxWatchdogTimer *t)