Fix problem with different pointer sizes for code and data types.

	* gdb/avr-tdep.c (struct gdbarch_tdep): Add back types for code
	and data.
	(avr_register_type): Use AVR arch specific types for code and data
	pointers.
	(avr_make_code_addr): Use flag bits with both addresses and pointers.
	(avr_make_code_ptr): Likewise.
	(avr_make_data_addr): Likewise.
	(avr_make_data_ptr): Likewise.
	(avr_address_to_pointer): Use hex_string rather than
	print_core_address.
	(avr_pointer_to_address): Likewise.
	(avr_gdbarch_init): Initialize custom types.
	(avr_dump_tdep): Print custom types.