Replace homegrown PID file functions with std BSD pidfile()

- Import pidfile() v1.11 from OpenBSD and libite (-lite) project
- Import utimensat() replacement, for systems that don't have it
- Simplify syslogd and klogd program start and PID file creation
- Rip out -i and -I from klogd, uses old PID file functions, and
  they're only kill(1) wrappers anyway

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

configure.ac

@@ -40,7 +40,7 @@ AC_HEADER_STDC
 PKG_PROG_PKG_CONFIG
 
 # Check for usually missing API's, which we can replace
-AC_REPLACE_FUNCS([strlcpy strlcat])
+AC_REPLACE_FUNCS([pidfile strlcpy strlcat utimensat])
 AC_CONFIG_LIBOBJ_DIR([lib])
 
 # Command line options