PM / hibernate: use unsigned local variables in swsusp_show_speed()

do_div() needs 'u64' type, or it reports warning. And negative number
is meaningless for "speed", so change all signed to unsigned within
swsusp_show_speed().

The related warning (with allmodconfig for unicore32):

    CC      kernel/power/hibernate.o
  kernel/power/hibernate.c: In function ‘swsusp_show_speed’:
  kernel/power/hibernate.c:237: warning: comparison of distinct pointer types lacks a cast
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
[rjw: Subject]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

kernel/power/hibernate.c

@@ -228,19 +228,23 @@ static void platform_recover(int platform_mode)
 void swsusp_show_speed(struct timeval *start, struct timeval *stop,
 			unsigned nr_pages, char *msg)
 {
-	s64 elapsed_centisecs64;
-	int centisecs;
-	int k;
-	int kps;
+	u64 elapsed_centisecs64;
+	unsigned int centisecs;
+	unsigned int k;
+	unsigned int kps;
 
 	elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start);
+	/*
+	 * If "(s64)elapsed_centisecs64 < 0", it will print long elapsed time,
+	 * it is obvious enough for what went wrong.
+	 */
 	do_div(elapsed_centisecs64, NSEC_PER_SEC / 100);
 	centisecs = elapsed_centisecs64;
 	if (centisecs == 0)
 		centisecs = 1;	/* avoid div-by-zero */
 	k = nr_pages * (PAGE_SIZE / 1024);
 	kps = (k * 100) / centisecs;
-	printk(KERN_INFO "PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n",
+	printk(KERN_INFO "PM: %s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n",
 			msg, k,
 			centisecs / 100, centisecs % 100,
 			kps / 1000, (kps % 1000) / 10);