re PR bootstrap/17832 (Bootstrap broken by fixincludes failures)

	PR bootstrap/17832

	* fixincl.c (SIGCHLD): Remove definition.
	(initialize): Remove SIGIOT and SIGPIPE checks.
	(create_file): Fix mkdir() for Win32.
	(internal_fix): Use dup2() instead of fcntl().

	* fixlib.h (SIGQUIT): Define if undefined.
	(SIGIOT): Same.
	(SIGPIPE): Same.
	(SIGALRM): Same.
	(SIGKILL): Same.

	* procopen.c (chain_open): Use dup2() instead of fcntl().

From-SVN: r89326