Add firmware 10.2.4.70.9-2 which uses FW API 5 so use name firmware-5.bin. Keep
firmware-4.bin for backwards compatibility with older ath10k versions.
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
[bwh: Remove trailing whitespace from notice]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>