rockchip: Drop Ethernet from the TODO

Now that ethernet support works, it can be dropped from the rockchip
TODO

Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Acked-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Simon Glass <sjg@chromium.org>

doc/README.rockchip

@@ -219,7 +219,6 @@ Immediate priorities are:
 - USB host
 - USB device
 - Run CPU at full speed (code exists but we only see ~60 DMIPS maximum)
-- Ethernet
 - NAND flash
 - Support for other Rockchip parts
 - Boot U-Boot proper over USB OTG (at present only SPL works)