* gengtype.h (xvasprintf): New prototype.
	(xasprintf): New prototype.
	(struct outf): New.
	(get_output_file): Return an outf_p.
	(header_file): Is now an outf_p.
	(base_files): Now are outf_p.
	(oprintf): New.
	* gengtype.c: Replace all output FILE * with outf_p; use oprintf
	rather than stdio operations.  Use xasprintf in a few places,
	when appropriate.
	(xvasprintf): New.
	(xasprintf): New.
	(struct filemap): Delete.
	(files): Delete.
	(output_files): New.
	(oprintf): New.
	(create_file): Create an outf_p.  Add parameter to indicate output
	file name, change all callers.
	(open_base_files): Create gtype-desc.c here.
	(get_output_file_with_visibility): Rewrite.
	(get_output_file_name): Just look at 'name' field in struct outf.
	(close_output_files): Rewrite.

From-SVN: r54566