In runqemu-ifup, ip command is used to add TAP; in runqemu-ifdown,
we should do the reversed logic, using ip command to delete TAP, to
make sure TAP is cleaned up by ourselves.
I can see that in runqemu-ifdown script, 'tunctl -d' and 'iptables'
commands are used to deal with TAP, but these two commands cannot
make sure that the TAP is cleaned up.
runqemu-ifup uses 'ip' to set up TAP, we really need to do the opposite
in runqemu-ifdown.
Signed-off-by: Chen Qi <Qi.Chen@windriver.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
