Move common definitions for DNA Valokuitu Plus EX400 to a dtsi include.
This is in preparation of adding the non-branded variant of the device
produced by Genexis / Inteno in the next commit. The device with DNA
branding differs in the LED labling on the device.
Signed-off-by: Andreas Gnau <andreas.gnau@iopsys.eu>
Link: https://github.com/openwrt/openwrt/pull/17551
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>