UPSTREAM: selftests: timers: Fix posix_timers ksft_print_msg() warning

[ Upstream commit e4a6bcea ]

After commit 6d029c25 ("selftests/timers/posix_timers: Reimplement
check_timer_distribution()") the following warning occurs when building
with an older gcc:

posix_timers.c:250:2: warning: format not a string literal and no format arguments [-Wformat-security]
  250 |  ksft_print_msg(errmsg);
      |  ^~~~~~~~~~~~~~

Fix this up by changing it to ksft_print_msg("%s", errmsg)

Fixes: 6d029c25 ("selftests/timers/posix_timers: Reimplement check_timer_distribution()")
Change-Id: I003cc201f413e6972358fcf2b4c99583d11f391d
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Justin Stitt <justinstitt@google.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240410232637.4135564-1-jstultz@google.com


Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit fe09b8d2)
Signed-off-by: Edward Liaw <edliaw@google.com>