Documentation/osnoise: Escape underscore of NO_ prefix

kernel test robot reported unknown target name warning:

Documentation/trace/osnoise-tracer.rst:112: WARNING: Unknown target name: "no".

The warning causes NO_ prefix to be rendered as link text instead, which
points to non-existent link target.

Escape the prefix underscore to fix the warning.

Link: https://lkml.kernel.org/r/20221125034300.24168-1-bagasdotme@gmail.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Cc: GNU/Weeb Mailing List <gwml@vger.gnuweeb.org>
Link: https://lore.kernel.org/linux-doc/202211240447.HxRNftE5-lkp@intel.com/
Fixes: 67543cd6 ("Documentation/osnoise: Add osnoise/options documentation")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Documentation/trace/osnoise-tracer.rst

@@ -111,7 +111,7 @@ The tracer has a set of options inside the osnoise directory, they are:
    be used, which is currently 5 us.
  - osnoise/options: a set of on/off options that can be enabled by
    writing the option name to the file or disabled by writing the option
-   name preceded with the 'NO_' prefix. For example, writing
+   name preceded with the 'NO\_' prefix. For example, writing
    NO_OSNOISE_WORKLOAD disables the OSNOISE_WORKLOAD option. The
    special DEAFAULTS option resets all options to the default value.