Fix overflow in time2tick / tick2time.

The helper functions gets passed an unsigned int, which gets cast to long
and overflows. See http://bugs.debian.org/175462Signed-off-by: Andreas Henriksson <andreas@fatal.se>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>

tc/tc_core.c

@@ -35,12 +35,12 @@ int tc_core_time2big(long time)
 }
 
 
-long tc_core_time2tick(long time)
+unsigned tc_core_time2tick(unsigned time)
 {
 	return time*tick_in_usec;
 }
 
-long tc_core_tick2time(long tick)
+unsigned tc_core_tick2time(unsigned tick)
 {
 	return tick/tick_in_usec;
 }

tc/tc_core.h

@@ -7,8 +7,8 @@
 #define TIME_UNITS_PER_SEC	1000000
 
 int  tc_core_time2big(long time);
-long tc_core_time2tick(long time);
-long tc_core_tick2time(long tick);
+unsigned tc_core_time2tick(unsigned time);
+unsigned tc_core_tick2time(unsigned tick);
 long tc_core_time2ktime(long time);
 long tc_core_ktime2time(long ktime);
 unsigned tc_calc_xmittime(unsigned rate, unsigned size);