when runqemu with slirp option on same host with different
users, it will report PermissionError: [Errno 13] Permission
denied: '/tmp/qemu-port-locks/2222.lock'
and during handle this exception, another exception happened since
key not exist. Fix by check if key exist first
Signed-off-by: Changqing Li <changqing.li@windriver.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
