fio: fix overflow trying to use 'd' suffix

Fix overflow that happened when using the 'd' time suffix on platforms
with 32 bit longs which led to a time of less than 10 minutes being
used.

Author: sitsofe

parse.c

@@ -167,7 +167,7 @@ static unsigned long long get_mult_time(const char *str, int len,
 	else if (!strcmp("h", c))
 		mult = 60 * 60 * 1000000UL;
 	else if (!strcmp("d", c))
-		mult = 24 * 60 * 60 * 1000000UL;
+		mult = 24 * 60 * 60 * 1000000ULL;
 
 	free(c);
 	return mult;