Since TUNE_FEATURES now either contains a CPU or an architecture (but
not both) we can't rely on finding the architecture in TUNE_FEATURES.
Use architecture specific over-rides instead.
(From OE-Core rev: 805dd4807d322dc70cef97edd68fdb3142b60fb1)
Signed-off-by: Andre McCurdy <armccurdy@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>