* srec.c (MAXCHUNK, Chunk): Revise comments.

	* srec.c (MAXCHUNK, Chunk): Revise comments.
	(srec_write_record): Correct buffer size.
	(srec_write_header): Do without intermediate buffer.
	(srec_write_section): Validate Chunk.
	(srec_write_terminator): Pass NULL instead of dummy buffer.
	(srec_write_symbols): Pass file and symbol names directly to
	bfd_bwrite so sprintf won't overflow buffer.