Documentation/rtla: Add include common_appendix.rst

JIRA: https://issues.redhat.com/browse/RHEL-117873

commit f44f944
Author: Costa Shulyupin <costa.shul@redhat.com>
Date:   Sun Jun 8 13:44:36 2025 +0300

    Documentation/rtla: Add include common_appendix.rst

    Add include common_appendix.rst into
    Documentation/tools/rtla/rtla-timerlat-hist.rst - the only file of
    rtla-*.rst still without common_appendix.rst.

    Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
    Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
    Signed-off-by: Jonathan Corbet <corbet@lwn.net>
    Link: https://lore.kernel.org/r/20250608104437.753708-2-costa.shul@redhat.com

Signed-off-by: Tomas Glozar <tglozar@redhat.com>

Author: lenticularis39

Documentation/tools/rtla/rtla-timerlat-hist.rst

@@ -107,3 +107,5 @@ SEE ALSO
 AUTHOR
 ======
 Written by Daniel Bristot de Oliveira <bristot@kernel.org>
+
+.. include:: common_appendix.rst