ath79: D-Link DAP-2660 A1: convert ath10k caldata to nvmem

ath79: D-Link DAP-2660 A1: convert ath10k caldata to nvmem

Add the PCIe node for the ath10k radio to the devicetree, and refer to
the art partition for the calibration data using nvmem-cells.

MAC address assignment is moved to '10_fix_wifi_mac', so the device can
then be removed from the caldata extraction script '11-ath10k-caldata'.

Cc: Sebastian Schaper <openwrt@sebastianschaper.net>
Tested-by: Sebastian Schaper <openwrt@sebastianschaper.net>
Signed-off-by: Sander Vanheule <sander@svanheule.net>