This variable has been unused since the tune file overhaul two years
ago.
(From OE-Core rev: a1d9f2374ede768057fd364da6c0e1eeeb10499f)
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>