* getloadavg.c: Include fcntl--.h rather than fcntl.h.

* getloadavg.c: Include fcntl--.h rather than fcntl.h.
Do not include unistd-safer.h.
(getloadavg): Don't call fd_safer; no longer needed
now that we include fcntl--.h.
* getloadavg.c:
Assume HAVE_UNISTD_H, i.e., include <unistd.h> unconditionally.
Assume HAVE_FCNTL_H (i.e., include <fcntl.h> unconditionally,
and don't include <sys/file.h>).
* getloadavg.c (getloadavg) [__CYGWIN__]: Port to cygwin.
[__linux__]: Allocate a big enough buffer for /proc/loadavg.
[!LDAV_DONE]: Avoid unused variable warning.