ath9k: nvmem for ath9k caldata

ath9k: nvmem for ath9k caldata

With "getting WIFI MAC from NVMEM" working on ath79 on 5.10,
the next logical step I think is to utilize nvmem subsystem
to also get the calibration data from there.

This will tremendously speed up the wifi bring-up, since
we no longer need the userspace helper for the simple
devices that can just load them from there.

included with this patch is a package/mac80211/refresh.

Tested on: WNDR3700v2, TP-Link Archer C7v2

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>