avr/objdump: Support dumping .avr.prop section.

avr/objdump: Support dumping .avr.prop section.

Add support to objdump for dumping the .avr.prop section in a structured
way.

binutils/ChangeLog:

	* od-elf32_avr.c: Add elf32-avr.h include.
	(OPT_AVRPROP): Define.
	(options[]): Add 'avr-prop' entry.
	(elf32_avr_help): Add avr-prop help text.
	(elf32_avr_dump_avr_prop): New function.
	(elf32_avr_dump): Add check for avr-prop.

bfd/ChangeLog:

	* elf32-avr.h (struct avr_property_header): New strucure.
	(avr_elf32_load_property_records): Declare.
	(avr_elf32_property_record_name): Declare.
	* elf32-avr.c: Add bfd_stdint.h include.
	(retrieve_local_syms): New function.
	(get_elf_r_symndx_section): New function.
	(get_elf_r_symndx_offset): New function.
	(internal_reloc_compare): New function.
	(struct avr_find_section_data): New structure.
	(avr_is_section_for_address): New function.
	(avr_find_section_for_address): New function.
	(avr_elf32_load_records_from_section): New function.
	(avr_elf32_load_property_records): New function.
	(avr_elf32_property_record_name): New function.

gas/testsuite/ChangeLog:

	* gas/avr/avr-prop-1.d: New file.
	* gas/avr/avr-prop-1.s: New file.