docs: networking: convert ip-sysctl.txt to ReST

- add SPDX header;
- adjust titles and chapters, adding proper markups;
- mark code blocks and literals as such;
- mark lists as such;
- mark tables as such;
- use footnote markup;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/Documentation/networking/index.rst b/Documentation/networking/index.rst
index 3efb4608649a..7d133d8dbe2a 100644
--- a/Documentation/networking/index.rst
+++ b/Documentation/networking/index.rst
@@ -69,6 +69,7 @@ Contents:
    ip_dynaddr
    iphase
    ipsec
+   ip-sysctl
 
 .. only::  subproject and html