We never shipped the reference data in the source tree because it's
quite big (64M). As a result the only option is to generate it
locally. Although we have a rule to generate the reference file we
missed the dependency and location changes, probably because it's only
run for SLOW test runs.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>