clock_settime03: change to use CLOCK_REALTIME

CLOCK_REALTIME_ALARM requires an RTC with alarm support, which may not be
present on a system. In that case, the kernel will return EOPNOTSUPP, which
is defined as ENOTSUP in userspace.

Here use CLOCK_REALTIME instead of the CLOCK_REALTIME_ALARM because we do
NOT need suspend the SUT during test.

For issue #712:
  #712

Signed-off-by: Li Wang <liwang@redhat.com>
Cc: Viresh Kumar<viresh.kumar@linaro.org>
Cc: Cyril Hrubis <chrubis@suse.cz>
Cc: Jan Stancek <jstancek@redhat.com>
Tested-by: Li Wang <liwang@redhat.com>
Reviewed-by: Cyril Hrubis <chrubis@suse.cz>

Author: wangli5665

testcases/kernel/syscalls/clock_settime/clock_settime03.c

@@ -65,7 +65,7 @@ static void run(void)
 	SAFE_SIGADDSET(&set, SIGABRT);
 	SAFE_SIGPROCMASK(SIG_BLOCK, &set, NULL);
 
-	TEST(tst_syscall(__NR_timer_create, CLOCK_REALTIME_ALARM, &ev, &timer));
+	TEST(tst_syscall(__NR_timer_create, CLOCK_REALTIME, &ev, &timer));
 	if (TST_RET != 0)
 		tst_brk(TBROK | TERRNO, "timer_create() failed");