* agent/agent.h (agent_raw_key_from_file): Add R_KEYMETA argument.
(agent_update_private_key): New.
* agent/command-ssh.c (data_sign): Follow the change of the function
agent_raw_key_from_file.
* agent/command.c (do_one_keyinfo): Likewise.
(cmd_keyattr): New.
(register_commands): Add an entry of cmd_keyattr.
* agent/findkey.c (agent_update_private_key): New.
(agent_raw_key_from_file): Add R_KEYMETA argument.