brcmfmac: fix clearing wowl wake indicators

Newer firmwares require the usage of the wowl wakeind struct as size
for the iovar to clear the wake indicators. Older firmwares do not
care, so change the used size.

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