gcov.c: Tidy.

gcov.c: Tidy.

	* gcov.c: Tidy.
	(struct line_info, struct coverage): New structures.
	(gcov_file_name, gcov_file): Remove globals.
	(output_data): Take source file parameter. Fix memory leak. Break
	up into ...
	(init_line_info, output_line_info, make_gcov_file_name,
	accumulate_branch_counts): ... here.
	(calculate_branch_probs, function_summary): Adjust.
	(main): Adjust.
	(function_*): Remove global variables.

From-SVN: r56080