ath79-generic: add support for Onion Omega (#2306)

* ath79-generic: add support for Onion Omega

support was previously dropped in
commit 45c84a117b ("ar71xx: drop target")

* fixup! ath79-generic: add support for Onion Omega

* fixup! ath79-generic: add support for Onion Omega

docs/user/supported_devices.rst

@@ -25,6 +25,10 @@ ath79-generic
 
   - Raccoon
 
+* Onion
+
+  - Omega [#modular_ethernet]_
+
 * Plasma Cloud
 
   - PA300
@@ -327,3 +331,10 @@ Footnotes
 
 .. [#lan_as_wan]
   All LAN ports on this device are used as WAN.
+
+.. [#modular_ethernet]
+  These devices follow a modular principle,
+  which means even basic functionality like ethernet is provided by an expansion-board,
+  that may not be bundled with the device itself.
+  Such expansions are recommended for the config mode, but are not strictly necessary,
+  as exposed serial ports may grant sufficient access as well.

targets/ath79-generic

@@ -74,6 +74,12 @@ device('ocedo-raccoon', 'ocedo_raccoon', {
 	factory = false,
 })
 
+-- Onion
+
+-- modular/optional "ethernet expansion board" recommended for config mode
+-- setup via integrated (USB-)tty is possible as well
+device('onion-omega', 'onion_omega')
+
 -- Plasma Cloud
 
 device('plasma-cloud-pa300', 'plasmacloud_pa300')