brcmfmac: use provided channels for scheduled scan

User-space can provide list of channels in the schedule scan request.
This was ignored so all channels supported and allowed by the device
were used. This patch configures the device to use the channels as
listed in the request.

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>