selftests: timers: clocksource-switch: sort includes

It is easier to check if you need to add an include if the existing ones
are sorted.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: John Stultz <jstultz@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/timers/clocksource-switch.c

@@ -23,17 +23,17 @@
  */
 
 
+#include <fcntl.h>
 #include <stdio.h>
-#include <unistd.h>
 #include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/timex.h>
-#include <time.h>
 #include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <string.h>
 #include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
 #include "../kselftest.h"