libct: Create: rm unneeded chown

Commit 7cfb107f2c started using unix.Geteuid(), unix.Getegid() as
uid/gid argument for chown. It seems that it should have removed chown
entirely, since, according to mkdir(2),

> The newly created directory will be owned by the effective user ID of
> the process. If the directory containing the file has the
> set-group-ID bit set, or if the filesystem is mounted with BSD
> group semantics (mount -o bsdgroups or, synonymously mount -o grpid),
> the new directory will inherit the group ownership from its parent;
> otherwise it will be > owned by the effective group ID of the process.

So, the only effect of the chown after mkdir is ignoring the sgid bit
on the parent directory (which is probably not the right thing to do).

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

libcontainer/factory_linux.go

@@ -198,9 +198,6 @@ func (l *LinuxFactory) Create(id string, config *configs.Config) (Container, err
 	if err := os.MkdirAll(containerRoot, 0o711); err != nil {
 		return nil, err
 	}
-	if err := os.Chown(containerRoot, unix.Geteuid(), unix.Getegid()); err != nil {
-		return nil, err
-	}
 	c := &linuxContainer{
 		id:            id,
 		root:          containerRoot,