* gpgsm.c (main): Use GNUPG_DEFAULT_HOMEDIR constant.
* call-agent.c (start_agent): Create and pass the list of FD to
keep in the child to assuan.
* call-dirmngr.c (start_dirmngr): Ditto.
* scdaemon.c (main): Use GNUPG_DEFAULT_HOMEDIR constant.
* assuan-pipe-connect.c (assuan_pipe_connect): No special handling
for the log_fd and stderr.  Connect stderr to /dev/null if it
should not be retained.