Clarify the operation is not for command-line api
Clarify the operation is not for command-line api

Replace: https://github.com/opencontainers/runtime-spec/pull/447

Signed-off-by: Qiang Huang <488e06933c295c76472a67dbc6657ac40a756953@huawei.com>

opencontainers/runtime-spec,hqhq/specs,laijs/specs,opencontainers/specs,hqhq/runtime-spec,cloudfoundry-incubator/specs,wking/opencontainer-specs,wking/opencontainer-runtime-spec,ujuc/specs,vbatts/specs,jonboulle/specs