Add firmware file and licence for Intel Broadwell SST DSP audio.
The firmware is distributed under Intel Free Redistribution License.

Signed-off-by: Jie Yang <yang.jie@intel.com>
(cherry picked from linux-firmware@kernel.org)
Signed-off-by: Kevin Strasser <kevin.strasser@intel.com>

BUG=chrome-os-partner:33022
TEST=LPE audio works on Broadwell

Change-Id: Ib7d721f9785a1428649ec43c2a46f1871085db40
Reviewed-on: https://chromium-review.googlesource.com/228921


Reviewed-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Ben Zhang <benzh@chromium.org>
Commit-Queue: Ben Zhang <benzh@chromium.org>
Tested-by: Ben Zhang <benzh@chromium.org>