tests/tcg: don't append QEMU_OPTS for armv6m-undef test

We don't want to build on the default machine setup here but define a
custom one for the microbit.

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240514174253.694591-2-alex.bennee@linaro.org>
1 file changed