mac80211: Backport AR934x OTP Patch

Merged upstream in https://patchwork.kernel.org/patch/9572541/

, this
patch fixes the OTP offset used by the AR934x and AR955X to properly
enable reading from the OTP.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Chris Blake <chrisrblake93@gmail.com>