selftest/timers: Remove duplicate header

Remove duplicate header which is included twice.
Signed-off-by: NSabyasachi Gupta <sabyasachi.linux@gmail.com>
Signed-off-by: NSouptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: NShuah Khan <shuah@kernel.org>

tools/testing/selftests/timers/skew_consistency.c

@@ -32,7 +32,6 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
-#include <stdlib.h>
 #include <string.h>
 #include <sys/wait.h>
 #include "../kselftest.h"