arm64: dts: allwinner: h6: tanix-tx6: Add IR remote mapping

Tanix TX6 box comes with a remote. Add a mapping for it.

Suggested-by: Michael Lange <linuxstuff@milaw.biz>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>