Documentation/rtla: Add hwnoise man page

Add a man page for the new rtla hwnoise tool, mostly based in the
rtla osnoise top.

Link: https://lkml.kernel.org/r/27088e0f42a6129e9b75f789d78adff4171f2e79.1675805361.git.bristot@kernel.org



Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>