The BDFs for all boards were upstreamed to the ath10k-firmware
repository and are now part of ath10k-firmware 2018-04-19.
We switched to the upstream board-2.bin, hence the files can be removed
here.
Keep the ipq-wifi package in case new boards are added. It might take
some time till board-2.bins send upstream are merged.
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>