docs: networking: convert defza.txt to ReST

Not much to be done here:

- add SPDX header;
- add a document title;
- use :field: markup for the version number;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/defza.txt → Documentation/networking/defza.rst

-Notes on the DEC FDDIcontroller 700 (DEFZA-xx) driver v.1.1.4.
+.. SPDX-License-Identifier: GPL-2.0
+
+=====================================================
+Notes on the DEC FDDIcontroller 700 (DEFZA-xx) driver
+=====================================================
+
+:Version: v.1.1.4
 
 
 DEC FDDIcontroller 700 is DEC's first-generation TURBOchannel FDDI

Documentation/networking/index.rst

@@ -51,6 +51,7 @@ Contents:
    dccp
    dctcp
    decnet
+   defza
 
 .. only::  subproject and html