lxcapi_create: don't delete if container rootfs already exists

If lxc.rootfs is specified, we believe rootfs is ready. lxc-start will
check this later. Return true, because the container is created.

Signed-off-by: Sheng Yong <shyodx@gmail.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
lxc-create: fix conflict of rootfs.path and template default path

1. rootfs.path set, -t not set: rootfs.path is rootfs path
2. rootfs.path set, -t set: change template default path to rootfs path
3. rootfs.path not set, -t set: template default path is rootfs path
4. rootfs.path not set, -t not set: error
5. rootfs.path set but cannot access: error

Signed-off-by: Sheng Yong <shyodx@gmail.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
api_create and do_bdev_create: a few more fixes

don't use lxcpath variable for rootfs_path, it's confusing.

if rootfs is passed in and tpath is passed in, return error
before we save a new config, and don't delete the container

make sure to check c->lxc_conf is not NULL before dereferencing it.

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>