Older ath79-based MikroTik devices have the ERD calibration data
compressed and stored different to newer IPQ40xx ones. This commit
adds support for these former ones.
Signed-off-by: Roger Pueyo Centelles <roger.pueyo@guifi.net>
Acked-by: Koen Vandeputte <koen.vandeputte@ncentric.com>