agent: Terminate on deletion of the socket file (Linux only).
* configure.ac (AC_CHECK_FUNCS): Chec for inotify_init. * agent/gpg-agent.c [HAVE_INOTIFY_INIT]: Include sys/inotify.h. (my_inotify_is_name) [HAVE_INOTIFY_INIT]: New. (handle_connections) [HAVE_INOTIFY_INIT]: New.
- Signed-off-by: Werner Koch <wk@gnupg.org>