ASoC: SOF: Intel: bdw: Set the mailbox offset directly in bdw_probe

ASoC: SOF: Intel: bdw: Set the mailbox offset directly in bdw_probe

To align with other platforms, set only the sdev->dsp_box.offset in
bdw_probe().
The mailbox offset must be set in order to be able to receive the firmware
ready message.

The offsets and sizes will be re-configured after the FW ready message
based on the window information.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20210915122116.18317-2-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>