tests/avocado: partially revert unmasking of replay_linux tests

It seems we were premature in declaring replay_linux.py fixed. The
x86_64 image still seems to hang occasionally. I've raised a new bug
to cover it:

    https://gitlab.com/qemu-project/qemu/-/issues/2094

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
1 file changed