Replaced get_tick_per_sec() by NANOSECONDS_PER_SECOND

This patch replaces get_ticks_per_sec() calls with the macro
NANOSECONDS_PER_SECOND. Also, as there are no callers, get_ticks_per_sec()
is then removed.  This replacement improves the readability and
understandability of code.

For example,

    timer_mod(fdctrl->result_timer,
	      qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (get_ticks_per_sec() / 50));

NANOSECONDS_PER_SECOND makes it obvious that qemu_clock_get_ns
matches the unit of the expression on the right side of the plus.

Signed-off-by: Rutuja Shah <rutu.shah.26@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/hw/timer/pxa2xx_timer.c b/hw/timer/pxa2xx_timer.c
index 33449e6..59002b4 100644
--- a/hw/timer/pxa2xx_timer.c
+++ b/hw/timer/pxa2xx_timer.c
@@ -119,11 +119,11 @@
     uint64_t new_qemu;
 
     now_vm = s->clock +
-            muldiv64(now_qemu - s->lastload, s->freq, get_ticks_per_sec());
+            muldiv64(now_qemu - s->lastload, s->freq, NANOSECONDS_PER_SECOND);
 
     for (i = 0; i < 4; i ++) {
         new_qemu = now_qemu + muldiv64((uint32_t) (s->timer[i].value - now_vm),
-                        get_ticks_per_sec(), s->freq);
+                        NANOSECONDS_PER_SECOND, s->freq);
         timer_mod(s->timer[i].qtimer, new_qemu);
     }
 }
@@ -148,10 +148,10 @@
 
     now_vm = s->tm4[counter].clock + muldiv64(now_qemu -
                     s->tm4[counter].lastload,
-                    s->tm4[counter].freq, get_ticks_per_sec());
+                    s->tm4[counter].freq, NANOSECONDS_PER_SECOND);
 
     new_qemu = now_qemu + muldiv64((uint32_t) (s->tm4[n].tm.value - now_vm),
-                    get_ticks_per_sec(), s->tm4[counter].freq);
+                    NANOSECONDS_PER_SECOND, s->tm4[counter].freq);
     timer_mod(s->tm4[n].tm.qtimer, new_qemu);
 }
 
@@ -190,7 +190,7 @@
         return s->tm4[tm].tm.value;
     case OSCR:
         return s->clock + muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
-                        s->lastload, s->freq, get_ticks_per_sec());
+                        s->lastload, s->freq, NANOSECONDS_PER_SECOND);
     case OSCR11: tm ++;
         /* fall through */
     case OSCR10: tm ++;
@@ -214,15 +214,17 @@
                 s->snapshot = s->tm4[tm - 1].clock + muldiv64(
                                 qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
                                 s->tm4[tm - 1].lastload,
-                                s->tm4[tm - 1].freq, get_ticks_per_sec());
+                                s->tm4[tm - 1].freq, NANOSECONDS_PER_SECOND);
             else
                 s->snapshot = s->tm4[tm - 1].clock;
         }
 
         if (!s->tm4[tm].freq)
             return s->tm4[tm].clock;
-        return s->tm4[tm].clock + muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
-                        s->tm4[tm].lastload, s->tm4[tm].freq, get_ticks_per_sec());
+        return s->tm4[tm].clock +
+            muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
+                     s->tm4[tm].lastload, s->tm4[tm].freq,
+                     NANOSECONDS_PER_SECOND);
     case OIER:
         return s->irq_enabled;
     case OSSR:	/* Status register */