* config/unix-gdb.exp (gdb_exit): Remove close commands that

	* config/unix-gdb.exp (gdb_exit):  Remove close commands that
	may be called after gdb goes away.  Previous versions of expect
	needed these to avoid file descriptor leaks, but they cause
	errors with the current revision of expect.
	* gdb.t00/gdbvars.exp:  Use -re on expected output after
	setting sevenbit-strings.
	* gdb.t04/setvar.exp, gdb.t13/bitfields.exp:  Make commands
	to set sevenbit-strings consistent across tests.
	**** start-sanitize-chill ****
	gdb.t30/chexp.exp, gdb.t31/chillvars.exp:  Make commands to
	set sevenbit-strings consistent across tests.
	**** end-sanitize-chill ****