All containers except the pause container, mount `/dev/shm" with flags
`nosuid,nodev,noexec`. So change mount options for pause container to
keep consistence.
This also helps to solve issues of failing to mount `/dev/shm` when
pod/container level user namespace is enabled.
Fixes: #6911
Signed-off-by: Jiang Liu <gerry@linux.alibaba.com>
Signed-off-by: Lei Wang <wllenyj@linux.alibaba.com>
42a386c816