timer: Move NANOSECONDS_PER_SECONDS to timer.h

We want to be able to reuse this define by making it common to
multiple QEMU modules.

This also makes it an integer since there's no need for it to be a
float.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 6375912849da2ab561046dd013684535ccecca44.1434113783.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

include/qemu/throttle.h

@@ -29,8 +29,6 @@
 #include "qemu-common.h"
 #include "qemu/timer.h"
 
-#define NANOSECONDS_PER_SECOND  1000000000.0
-
 typedef enum {
     THROTTLE_BPS_TOTAL,
     THROTTLE_BPS_READ,

include/qemu/timer.h

@@ -5,6 +5,8 @@
 #include "qemu-common.h"
 #include "qemu/notify.h"
 
+#define NANOSECONDS_PER_SECOND 1000000000LL
+
 /* timers */
 
 #define SCALE_MS 1000000