Always define off_t, mode_t, pid_t

	* io/fcntl.h: Always define mode_t, off_t, pid_t and use these
	types for creat, creat64, lockf, posix_fadvise, posix_fallocate.
	[__USE_LARGEFILE64 && !__off64_t_defined]: Define off64_t.
	[__USE_LARGEFILE64]: Use off64_t in declaration of lock64,
	posix_fadvise64, posix_fallocate64.