10139 smatch fixes for usr/src/cmd/stat

*** 9,18 ****
--- 9,22 ----
   */
  
  /* from UCB 5.4 5/17/86 */
  /* from SunOS 4.1, SID 1.31 */
  
+ /*
+  * Copyright (c) 2018, Joyent, Inc.
+  */
+ 
  #include <stdio.h>
  #include <stdlib.h>
  #include <stdarg.h>
  #include <ctype.h>
  #include <unistd.h>
*** 223,235 ****
          struct iodev_snapshot *new = (struct iodev_snapshot *)v2;
          hrtime_t oldtime = new->is_crtime;
          double hr_etime;
          double reads, writes;
  
-         if (new == NULL)
-                 return;
- 
          if (old)
                  oldtime = old->is_stats.wlastupdate;
          hr_etime = new->is_stats.wlastupdate - oldtime;
          if (hr_etime == 0.0)
                  hr_etime = NANOSEC;
--- 227,236 ----