rsi: remove kernel-doc comment marker

Change an errant kernel-doc comment marker (/**) to a regular
comment to prevent a kernel-doc warning.

rsi_91x.h:3: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Copyright (c) 2017 Redpine Signals Inc.

Fixes: 4c10d56a76bb ("rsi: add header file rsi_91x")
Signed-off-by: Randy Dunlap <[e-mail]>
Cc: Prameela Rani Garnepudi <[e-mail]>
Cc: Siva Rebbagondla <[e-mail]>
Acked-by: Kalle Valo <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

include/net/rsi_91x.h

···
-/**
+/*
  * Copyright (c) 2017 Redpine Signals Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any