time: ntp: simplify the MAX_TICKADJ_SCALED definition

Impact: cleanup, no functionality changed

There's an ugly u64 typecase in the MAX_TICKADJ_SCALED definition,
this can be eliminated by making the MAX_TICKADJ constant's type
64-bit (signed).

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2504	    114	    136	   2754	    ac2	ntp.o.before
   2504	    114	    136	   2754	    ac2	ntp.o.after

md5:
   41f3009debc9b397d7394dd77d912f0a  ntp.o.before.asm
   41f3009debc9b397d7394dd77d912f0a  ntp.o.after.asm
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/time/ntp.c

@@ -30,9 +30,9 @@ static u64			tick_length_base;
 
 static struct hrtimer		leap_timer;
 
-#define MAX_TICKADJ		500		/* usecs */
+#define MAX_TICKADJ		500LL		/* usecs */
 #define MAX_TICKADJ_SCALED \
-  (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
+	(((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
 
 /*
  * phase-lock loop variables