mount of /.dockerinit is not needed for native driver, so move it into lxc driver

Docker-DCO-1.1-Signed-off-by: Albert Zhang <zhgwenming@gmail.com> (github: zhgwenming)
since moved the ./dockerinit mount into lxc driver, fix the lxc testcase accordingly

Docker-DCO-1.1-Signed-off-by: Albert Zhang <zhgwenming@gmail.com> (github: zhgwenming)
Merge pull request #6797 from zhgwenming/master

make /.dockerinit bind mount driver specific