brcmfmac: allow wowlan support to be per device

The wowlan support is (partially) determined dynamic by checking the
device/firmware capabilities. So they can differ per device. So it
is not possible to use a static global. Instead use the global as a
template and use kmemdup(). When kmemdup() fails the template is used
unmodified.

Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>