[automerger skipped] Rename IDhcpLeaseCallbacks to IDhcpEventCallbacks for more generic. am: f8783184b0 -s ours

am skip reason: Change-Id Ia7b08bb1e7feda08ffe9fbb8885dbc8b7bdd66c9 with SHA-1 7d00387ead is in history

Change-Id: I97cdc5e3156fcbb31aedafc12ae4b6ec3ecdb85d