Merge pull request #2834 from freifunk-gluon/backport-2832-to-v2022.1.x

[Backport v2022.1.x] docs: readd TP-Link TD-W8970 v1 

docs/user/supported_devices.rst

@@ -237,6 +237,9 @@ lantiq-xrx200
   - FRITZ!Box 7362 SL [#eva_ramboot]_ [#lan_as_wan]_
   - FRITZ!Box 7412 [#eva_ramboot]_
 
+* TP-Link
+  - TD-W8970 (v1) [#lan_as_wan]_
+
 lantiq-xway
 -----------