docs: networking: device drivers: convert aquantia/atlantic.txt to ReST

- add SPDX header;
- use copyright symbol;
- adjust title and its markup;
- comment out text-only TOC from html/pdf output;
- mark code blocks and literals as such;
- adjust identation, whitespaces and blank lines where needed;
- 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/device_drivers/index.rst

@@ -30,6 +30,7 @@ Contents:
    3com/3c509
    3com/vortex
    amazon/ena
+   aquantia/atlantic
 
 .. only::  subproject and html
 

MAINTAINERS

@@ -1275,7 +1275,7 @@ L:	netdev@vger.kernel.org
 S:	Supported
 W:	https://www.marvell.com/
 Q:	http://patchwork.ozlabs.org/project/netdev/list/
-F:	Documentation/networking/device_drivers/aquantia/atlantic.txt
+F:	Documentation/networking/device_drivers/aquantia/atlantic.rst
 F:	drivers/net/ethernet/aquantia/atlantic/
 
 AQUANTIA ETHERNET DRIVER PTP SUBSYSTEM