ASoC: Intel: bxtn: optimize ROM init retries

During S3->S0 transition, sometime ROM init fails because of
authentication engine loads later than the OS. In this case driver
waits for a longer period and then retries the FW download causing
huge delay in resume time of audio device.

To avoid this, ROM INIT wait time is set to a optimal value and
increased the retries for firmware download.

Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>