The linux-yocto kernel and derivatives warn about WLAN_VENDOR_ATH
being set to 'm' when it's a boolean as of 5.13.x, update our
wifi.cfg fragment to fix that.
Bug-AGL: SPEC-3819
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: Ie524650ab20b70aefa37bfd3bbf499cd923185a1